POC Conf. Call 4-5-11

POC meeting, Webex Conference Call; Date: Tuesday Apr 5th, 2011 10am (PDT)

In attendance:

POC members: Laurel Cooper (OSU), Ramona Walls (NYBG), Justin Preece (OSU), Pankaj Jaiswal (OSU), Marie Alejandra Gandolfo (Cornell University), Barry Smith (University at Buffalo, NY)

Absent: Dennis Stevenson (NYBG), Justin Elser (OSU), Chris Mungall (Lawrence Berkeley National Lab)

Collaborators: None

Acceptance of the minutes from the POC_Conf._Call_3-29-11? There were no changes, additions, or deletions.

Tech issues

Report from JE about OBO to OWL conversion, and progress on has_parts?

Tabled till next week as JE was not present

Synonyms

RW: created two new synonym types: Spanish (range=exact) and Plural (range unspecified)

We have the list of Spanish synonyms from MAG, without accents, because AmiGO will not display accents properly. I am adding plurals as exact synonyms for terms that have different words in the plural (e.g., thallus-thalli, antheridium-antheridia) that may not show up in a search otherwise.

-LC: Suggestion: after the Spanish synonym, put (Sp), or something to that effect. Similarly,(pl)?

It appears that synonym types do not show up in AmiGO, so we may want to add (Sp) or (pl) or similar.

If we use ascii characters, they should display in all browsers. Will test this.

Next release?

If there is time for discussion this week.

We should aim for having all editing done by late April, so next PO database release can be in mid-May.

Need to have several weeks for users to review before release, especially Physco group.

BS suggested making document with what was changed in this release, and what is upcoming. We have been keeping a list of changes on our wiki which is available from the May_2011_Release_Page

*Need to concentrate on the priorities for this release:

-Fix embryonic and in vitro structures, (also portion of plant tissue)

-Rename PSO to PAO (easy to do on obo file, more work on web page and other uses)

Add physcomitrella terms

Issues arising from previous meetings:

in vitro plant structure

• At last week's meeting, We discussed whether or not we want the class for in vitro plant structures to only include plant structures that have not yet fully differentiated into tissues or organs (or whole plants, for that matter). PJ suggested that we could add a subclass of cultured callus for "differentiating callus" (if it can be defined correctly). It was suggested on the current definition could to be changed to reflect the fact that it should only include non-differentiated structures.

LC: I reopened the SF tracker for this do we can straighten this out.

• First of all, lets clarify the meaning of in vitro. This term has been in use in the scientific literature for at least 25 years or more.

There are various definitions available, and the direct translation from Latin means "under glass or within glass". (Of course, this has a historical connotation, most in vitro work now is done in plastics).

It is also defined as "outside of the body, in contrast to in vivo". This definition more closely fits the spirit of the above discussion and arises from the biomedical literature, where any in vitro work in the past, was not on the "whole body" for practical and or ethical reasons.

• I propose we follow the classical definition of in vitro, as there are numerous examples in the plant literature of whole plants grown in vitro.

For example: Insert image from Bohidar 2008.File:Bohidar et al 2008.pdf

Suggestion: in vitro structures should be children of their respective whole plant parts (cell, tissue, and embryo). Just like an embryonic plant cell is still a plant cell, an in vitro plant cell is still a plant cell.

LC requested the term "in_vitro growth" from PATO. after doing a pretty thorough search of the OBO ontologies and not found it, although it is used in MESH and the NCI Thesaurus. Suggested parent: is_a “growth quality of occurrent”

Suggested definition: A growth quality of occurrent in which the growth of an organism, structure or group of organisms involves microbe-free growth in a sterile environment.

LC has been surveying various ontologies for the term in vitro or in vitro growth: Suggested sources: OBI, PATO, GO

H. Parkinson of OBI suggested that PATO would be the most appropriate place and a term request was created. Unfortunately, it seems that PATO (G. Gkoutos) is planning on deprecating the class: “growth quality of occurrent” and suggested ENVO, GO or OBI. The particulars may change, depending upon the outcome of discussions that are underway with PATO, OBI and EFO, but the main ideas will stay essentially the same.

Proposed reorganization of the In vitro plant structure terms:

This example was based on the assumption that we would use a term such as "in vitro" or "in vitro growth" from PATO or OBI

Proposed PATO definition:

in vitro growth: A growth quality of occurrent in which the growth of an organism, structure or group of organisms involves microbe-free growth in a sterile environment.

comment: An example of a sterile culture environment is growth on or in a nutrient medium in a Petri dish or test tube. Microbes may be intentionally added to the culture environment, such as in co-culture with Agrobacterium.

*in vitro plant structure (PO:0000004): Current definition: A plant structure that was derived from part of a plant and involves microbe-free growth in a sterile environment.

Proposed def’n: A plant structure that is grown or maintained in vitro.

Comment: This is class is a cross-product of plant structure (PO:0009011) and in vitro growth ( requested in PATO:000XXXX).

*Cultured cell (PO:0000005): Current Def’n: In vitro grown, isolated cells and small cell aggregates that proliferate while suspended in liquid sterile medium or spread on a solid agar medium. [source: TAIR:ki]

Comment: In cell cultures, the cells are no longer organized into tissues.

Rename: cultured plant cell (PO:0000005)

Proposed def’n: A plant cell that is grown or maintained in vitro.

Comment: Includes isolated cells and small cell aggregates that proliferate while suspended in liquid sterile medium or spread on a solid agar medium. In cell cultures, the cells are no longer organized into tissues. This is class is a cross-product of plant cell (PO:0009002) and in vitro growth ( requested in PATO:000XXXX).

* cultured embryo (PO:0000010):

Current Def’n: In vitro isolated and maintained mature or immature zygotic embryos, somatic embryos or haploid embryos (derived from male gametophyte). [source: TAIR:ki]

Comment: None

Rename: cultured plant embryo (PO:0000010)

Proposed def’n: A plant embryo that is grown or maintained in vitro.

Comment: Includes isolated and maintained mature or immature zygotic embryos, somatic embryos or haploid embryos (derived from male gametophyte).

This is class is a cross-product of plant embryo (PO:0009009) and in vitro growth ( requested in PATO:000XXXX).

*cultured somatic embryo: (PO:0000011): Child of cultured plant embryo

Current Def’n: An embryo arising from previously differentiated somatic cells in vitro, rather than from fused haploid gametes, i.e., zygote. Proposed def’n: A plant somatic embryo that is grown or maintained in vitro. is_a: plant somatic embryo??

If cultured plant embryo is to be a child of embryo, we will need to adjust definition of embryo. Should talk to Melissa Haendel about how they handle haploid and diploid embryos in Zebrafish.

* cultured callus (PO:0000009): (note:fixed typo in name)

Current Def’n: In vitro grown cell aggregates that originated from isolated protoplasts, cell suspensions, or from callus that was induced in sterile medium supplemented by plant growth regulators.

Comment: None

cultured callus (PO:0000009): (Rename cultured plant callus?) yes

Proposed def’n: An in vitro plant structure consisting of a mass of undifferentiated plant cells.

Comment: Cultured callus may originate from isolated protoplasts, cell suspensions or from callus that was induced in sterile medium supplemented by plant growth regulators. Plant cell calluses may be made to differentiate into the specialized tissues of a whole plant, with the addition of a number of hormones or enzymes.

has_part cultured plant cells, is_a in_vitro plant structure

Problem: cannot be a portion of plant tissue: (A plant structure that has as its parts multiple cells and is a proper part of an organ).

* Children of cultured plant cell: these are more problematic:

cultured leaf cell (PO:0000007):

Current Def’n: In vitro grown isolated cells and small cell aggregates that originated from isolated leaf protoplasts (after they re-established cell wall, or from callus that was induced from leaf tissue).

cultured protoplast (PO:0000006):

Current Def’n: In vitro isolated cells from which the entire cell wall has been enzymatically removed.

cultured root cell (PO:0000008):

In vitro grown isolated cells and small cell aggregates that originated from isolated protoplasts after they re-established cell wall, or from callus that was induced from segment of root. What about a cell from a cultured root?

What about a whole plant or parts thereof that are grown in culture? Suppose someone had an annotation for a leaf from an in vitro grown plant. Where should they put it?

Also, we talked about using derived_from relations for in vitro structures (e.g., cultured cell derived_from plant cell). Do we still want to do that? How to assure that the derives from relations always hold?

Additional comments on today's discussions on in vitro structures:

PATO may deprecate growth quality branch. Perhaps in vitro growth should go into the Environment Ontology.

LC:Checked ENVO: not appropriate, I think

Checked EO: Has a term laboratory study, in vitro could be an is_a child?

BS pointed out that an in vitro grown plant is still a whole plant, just as fetus grown in a lab is still a fetus. However, there is some utility to distinguishing between in vitro plant structures that are growing ex situ (such as cultured cells or callus) and a plant structure that is part of a whole plant that is growing in vitro. In the latter case, annotations can be made to the plant structure in PO, plus another layer of annotation that describes the environment in which plants are grown.

There is still the grey area of, for example, a root that was induced from a callus in vitro. PJ felt that this should be annotated as a root, with the in vitro culture environment as a separate annotation.

We agreed to the new definition of in vitro plant structure proposed above in principle, but will have to work on exact definition, depending on whether or not we can use the term from another ontology.

We agreed that children of in vitro plant structure should be renamed as above and also be children of their respective plant structure. For example, cultured plant cell should be a child of plant cell (maybe parenchyma cell?).

Definition of portion of plant tissue will have to be revisited to accommodate tissues in plants without organs (like liverworts). Also, need to make sure definition of portion of plant tissue distinguishes it form cardinal organ part. Will either need to remove clause about being a proper part of a plant organ, so that cultured callus can go here, or only make cultured callus a child of in vitro plant structure.

Most in vitro plant structures could have dual parentage (is_a plant cell, tissue, whatever, and is_a in vitro plant structure). Can't use intersection_of terms b/c in vitro growth is not in PO.

We agreed that the children of cultured plant cell need to be renamed and possibly redefined to make it clearer what they are referring to. For example:

cultured leaf cell (PO:0000007) should be named leaf-derived cultured cell. Use this term if we don’t know what part of the leaf it is from. Could have, e.g., leaf-mesophyll-derived cultured cell as a child term.

Definition of cultured plant callus should say "a mass of undifferentiated parenchyma cells.

MAG supplied a definition of callus (in vivo) to insure that it is only composed of parenchyma cells: >From Eames and MacDaniels-- Introduction to Plant Anatomy

CALLUS: Among the important functions of the cambium is the formation of "callus" or "wound tissue" When wound occur in roots or stems, masses of soft parenchymatous tissue quickly from on or below the injured surface; this tissues is known as callus. Callus may be formed by the division of parenchyma cells on the phloem and the cortex, but its most frequent source is the cambium. The outer cells of this tissue either become suberized themselves or periderm develops within them, so that a protecting bark is formed beneath which the cambium is active and in forming new vascular tissue in the normal way.

On 4/6/2011 DWS commented by email: "This is true of both the cork and vascular cambia, the former also being termed the phellogen".

BS will send paper on how to deal with carcinomas. Solution may be similar for plant callus. See this citation: Smith et al, 2005

Smith, B., Kumar, A., Ceusters, W., and Rosse, C. (2005). On carcinomas and other pathological entities. Comp Funct Genom, 6, 379-387

Need to keep in mind callose, (note: distinct from 'callus') as a substance that is associated with sieve elements.

Callose: definition: A complex branched carbohydrate that is a common wall constituent associated with the sieve areas of sieve elements; may develop in reaction to injury in sieve elements and parenchyma cells. (Raven, Evert and Eichhorn, 4th edition)

From DWS by email: "Callose is not a structure, but rather a compound that occurs in the cell wall as a ring that surrounds the sieve pores. It is electron translucent in TEM. It also occur in the walls of pollen tubes. The plugs in the sieve pores are protein that becomes occlusive as the result a drastic changes in pressure a dure to wounding. The are actually artifacts."

mega/microspore

Unresolved question from 3-22-11:

Is is more accurate to say:

mega/microspore develops_from tetrad of mega/microspores

or

tetrad of mega/microspores has_part mega/microspore

We agree that it was better to use tetrad of mega/microspores has_part mega/microspore. A megaspore doesn't develop from the tetrad of spores, but rather is one of the spores in the tetrad.

ground tissue cell

ground tissue cell (PO:0025030) was added in the fall of 2010 to help organize plant cells. However, it was never defined.

Proposed definition: A plant cell that is part of a portion of ground tissue.

Comment: Includes parenchyma, collenchyma and sclerenchyma cells.

Synonym: Fundamental tissue cell

While we're at it, should redefine epidermal cell

current def: Cell that constitutes dermal tissue. [TAIR:ki]

proposed def: A plant cell that is part of a portion of epidermis.

Proposed definitions were accepted.

embryo

embryo (PO:0009009) current definition: A whole plant in the post-zygotic stage that does not yet consist of fully differentiated tissues.

Comment: Adventitious embryos and somatic embryos do not arise from zygotes. Cultured embryos (PO:0000010), including haploid embryos, are in vitro plant structures. Embryos occur prior to germination in vascular plants.

This is not really consistent with the fact that we have tissues like embryonic epidermis and embryonic cortex.

Proposed definition: A whole plant in the sporophytic phase that is contained in an archegonium or a seed.

Comment: The embryo is a whole plant after fertilization (post-zygotic) and before emergence from the archegonium (for bryophytes and pteridophytes) or seed germination (for seed plants). Adventitious embryos and somatic embryos do not arise from zygotes. Cultured embryos (PO:0000010), including haploid embryos, are in vitro plant structures.

Logically, an embryo could be treated like a sporophyte or gametophyte, that is, as a cross-product of whole plant and the appropriate life cycle phase. However, since we don't have embryonic phase yet, and since so much research is done on embryos, it may be appropriate to keep the class embryo, and pre-compose the cross-product once we have embryonic phase.

Could add zygotic and haploid embryo as children of embryo

Should talk to Melissa Haendel about how they handle haploid and diploid embryos in Zebrafish.

If we want cultured plant embryo to be a child of embryo, we will need to remove the comment here that they are in vitro plant structures.

Discussion of haploid embryos. Are they still in the sporophytic phase? RW: Yes, because they develop into haploid sporophytes, even if those sporophytes may be sterile. This happens naturally in many ferns and sometimes in bryophytes (apogamy - when a gametophyte gives rise to a sporophyte without syngamy). The reverse also happens (apospory -- when a sporophyte gives rise to a gametophyte without meiosis).

LC: Note: Haploid embryos cannot be considered in the sporophytic phase (as it it defined now), since they are not the product of fertilization.

embryonic plant structures

Tabled till next week

Definition of embryonic plant structure:

embryonic plant structure (PO:0025099): A plant structure that is part of an embryo.

Comment: Includes organs, tissues and cell types that are unique to embryos, not plant structures that can occur in both embryos and mature plant structures.

Changed definition from "proper part of" to "part of", so it would be consistent with the intersection of term. Think part_of is better anyway, because technically an embryo is an embryonic plant structure.

Some terms were left as is_a children of embryonic plant structure:

coleoptile (PO:0020033): A tubular embryonic plant structure developed at the junction of the cotyledonary sheath with the seedling axis, and surrounding the plumule of a monocot embryo or seedling.

embryo proper (PO:0000001): An embryonic plant structure that is the body of a developing embryo attached to the maternal tissue in an ovule by a suspensor.

scutellum (PO:0020110): An embryonic plant structure that is a more or less shield-shaped and absorptive portion of an embryo of Poaceae.

suspensor (PO:0020108): An embryonic plant structure at the base of an embryo that develops from a basal cell and connects an embryo proper to the wall of a megagametophyte.

New definitions for embryonic plant cells and tissues

Both now have cross-product definitions, and no asserted is_a children

embryonic plant cell (PO:0025028): A plant cell that is part of an embryo.

is_a embryonic plant structure, intersection_of: is_a plant cell, intersection_of: part_of embryo

Made apical cell (PO:0004000, now embryonic apical cell) is_a apical cell part_of embryo (still dev_from zygote). Should probably obsolete and replace with new term to avoid confusion

Made basal cell (PO:0002002, now embryonic basal cell) is_a plant cell, part of embryo (still dev_from zygote)

Made hypophysis (PO:0020109, now embryonic hypophysis) is_a plant cell, part_of embryo.

(portion of) embryonic plant tissue (PO:0025233): A portion of plant tissue that is part of an embryo.

is_a embryonic plant structure, intersection_of: is_a portion of plant tissue, intersection_of: part_of embryo

coleorhiza (PO:0020034), embryo cortex (PO:0005014), embryo epidermis (PO:0005015), embryonic shoot apical meristem (PO:0006362), epiblast (PO:0020036), scutellar epithelium (PO:0008048), and scutellum epidermis (PO:0006049) are now inferred children of embryonic plant tissue.

This is a little odd, because we define embryo (PO:0009009) as: "A whole plant in the post-zygotic stage that does not yet consist of fully differentiated tissues," but I guess there is nothing in the definition of epidermis or cortex, etc, that says that they are fully differentiated. May want to put a comment under embryonic tissue to that effect.

Technically, we could get rid of the is_a embryonic plant structure relation for both, because it would be inferred, but is makes it easier to work with the reasoner off when the relations are there.

Here is a picture of some plant tissues, to show how it works:

Proposed changes/questions for structures that were is_a embryonic plant structure:

embryonic leaf (PO:0006338): One of the first few leaves to develop from the embryonic shoot apical meristem [GR:pj].

Is this an embryonic plant structure, that is, is it always part of the embryo?

Proposed definition: A vascular leaf that is one of the first few leaves to develop from the embryonic shoot apical meristem and is part of an embryo.

is_a vascular leaf, part_of embryo (need to confirm part_of relation)

embryonic root (PO:0000045): An embryonic plant structure that is a root that is initiated in a developing embryo. [TAIR:ki]

Propose that this should be is_a root instead of is_a embryonic plant structure, b/c it is not necessarily part of an embryo.

Proposed definition: A root that is initiated in a developing embryo.

radicle (PO:0020031): The radicle is the basal continuation of the hypocotyl in an embryo and gives rise to the root system of the adult plant; sometimes more or less abortive. is_a embryonic root [APWeb:Glossary]

Proposed definition: An embryonic root that is the basal continuation of a hypocotyl in an embryo and may develop into the root system of an adult plant.

Comment: Sometimes abortive.

remove part_of embryo axis.

hypocotyl (PO:0020100): The part of the stem below the cotyledonary node and transitional to a root, found in a young sporophyte. [APWeb:Glossary]

currently is_a cardinal organ part, propose is_a stem internode (we didn't have this term before but do now)

Proposed definition: A stem internode that is the part of a stem below the cotyledonary node and transitional to a root.

is_a stem internode

epicotyl (PO:0020035): The first internode of a stem above the hypocotyl. In literature also used for the entire embryonic axis, consisting of several internodes, above the cotyledonary node. [APWeb:Glossary]

currently is_a embryonic plant structure, propose is_a stem internode (PO:0005005). Also, the second part of the current definition only adds ambiguity. Need to define it more precisely.

Proposed definition: The first stem internode above a hypocotyl.

mesocotyl (PO:0020037): The internode between the cotyledon or cotyledons and the leaf or leaves at the next node of a young sporophyte.

This definition sounds like the same thing as an epicotyl. Should they be synonyms?

made is_a stem internode

hypocotyl-root junction PO:0004724: A cardinal organ part that is the part of an embryonic axis where the radicle joins the hypocotyl.

Moved to is_a cardinal organ part. Will automatically be is_a embryonic plant structure b/c it is part of embryonic axis. Is this accurate? The hypocotyl-root junction remains after germination.

plumule(PO:0020032): A somewhat differentiated terminal bud in several embryo types above the cotyledonary node, in which one or more internodes and leaves or scales can be discerned in a primordial stage.

made is_a terminal bud, part_of embryo

scutellar node (PO:0004708): The region in of an embryo axis between the primary root (enclosed in the coleorhiza) and the plumule (enclosed in the coleoptile) to which the scutellum is attached. [MaizeGDB:lv]

Sounds like it should be is_a stem node.

Proposed definition: A stem node that is the part of an embryo axis where the scutellum is attached.

Comment: A scutellum is attached to an embryo axis between the primary root (enclosed in the coleorhiza) and the plumule (enclosed in the coleoptile).

is_a stem node, part_of embryo axis

New Physcomitrella and related terms

Collective plant structures:

vascular and non-vascular shoot systems

The Moss Ontology did not request these terms, but suggest adding them in order to classify shoot systems.

non-vascular shoot system: A shoot system that does not have as part vascular tissue.

comment: Does not have any xylem of phloem, but may have other conducting cells, such hydroids or leptoids. Can occur in both the gametophytic and sporophytic phases of non-vascular plants.

subsets for bryophytes

Could we use the relation "lacks_part"? Then we could define this class using intersection_of relations, which would be better. CL has used this (lack_plasma_membrane_part). Works better in OWL; translates into something like has_part exactly 0 (some Y).

Child of non-vascular shoot system will be gametophore (see below). A moss sprophyte could also be called a non-vascular shoot system. If we used the lacks_part relation and intersection_of relations, we could make gameotophore a child of shoot system, and the reasoner would infer it was a non-vascular shoot system.

Can't use participates_in gametophytic phase, because the sporophyte of a bryphyte doesn't have roots or vascular tissue.

vascular shoot system: A shoot system that has as part vascular tissue.

comment: Has xylem and/or phloem. Occurs only in the sporophytic phase of vascular plants.

participates_in sporophytic phase, has_part vascular system

If we accept these terms, suggest changing definitions of vascular leaf (PO:0009025) and non-vascular leaf (PO:0025075) to "A leaf that is part of a vascular/non-vascular shoot system. This would be better than the current definitions which reference their taxonomy (part of a vascular or non-vascular plant) and would help with reasoning.

root-bourne shoot system (PO:0004544) should be is_a vascular shoot system

gametophore

Definition supplied by Moss Ontology: The leafy moss plant. The gametophore is the adult form of the moss gametophyte and bearer of the sex organs (gametangia). Ref: Reski (1998): Development, genetics and molecular biology of mosses. Botanica Acta 111, 1-15.

Suggest is_a shoot system.

Proposed def.: A non-vascular shoot system that consists of the shoot axes and non-vascular leaves of a plant in the gametophytic phase.

participates_in gametophytic phase, develops_from gametophore bud

Comment: A gametophore is the leafy part of the gametophyte of mosses and leafy liverworts, excluding the protonema. Develop from buds that form on the protonema. Antheridia and archegonia arise on the gametophore.

subset for bryophytes

gametophore bud

The term "bud" has been requested: Def'n supplied by Moss Ontology: A structure produced by a caulonema and able to develop into a gametophore or a stem that includes an apical cell able to develop into a gametophore. The earliest recognizable stage of gametophore development. Ref: Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition and altered by David Cove

Suggest a new term gametophore bud. This could be a child of bud (PO:0000055: An undeveloped shoot system).

Proposed def'n: A bud that develops into a gametophore.

Comment: Occurs in mosses and leaf liverworts. Develops from a caulonema cell in mosses.

participates_in gametophytic phase, has_part gametophore apical cell

synonym: brown bud

thallus

From Parihar: A simple vegetative plant body not differentiated into root, stem and leaf, and lacking vascular tissues.

From Schofeld: A flattened gametophore in which no leaf-like organs dominate the structure.

Saying a thallus is a gametophore implies that it is a shoot system and therefore a collective plant structure (CPS). As a CPS, it must have more that one organ. This is not always true for a thallus (sometime they branch, so you could say they have multiple axes, but it is a stretch. Maybe better to classify it as a whole plant.

proposed def: A whole plant in the gametophytic phase that has a flat growth form and no distinct organs.

Comment: A thallus is a gametophyte of liverworts and pteridophytes and develops from a short-lived protonema. Roughly two dimensional growth results from division of a single apical cell. Thalli may be ribbon or heart shaped or almost filamentous. Although there are no distinct organs, there may be tissue differentiation and dichotomous branching.

Add prothallium as a broad synonym of thallus and as a narrow synonym of whole plant.

Other gametophyte terms

We need to keep in mind terms for other types of gametophytes, such as the subterranean, heterotrophic gametophytes of some ferns. RW, DWS, and MAG will maintain a list of terms that we don't need to add yet, but may want to add as time allows or need demands. Can use this list, for example, for writing a renewal of things that still need to be done.

apical cell

Moss Ontology has requested the term apical cell. Apical growth in byrophytes is via division of a single cell at the tip of the shoot apical meristem. They also requested shoot apical cell and phyllid apical cell.

Non-seed vascular plants can also have an apical cell, that is, a single dividing cell at the apex of a root or shoot.

We already have the term apical cell (PO:0004000), which is an embryonic cell: "An embryonic plant cell that is the uppermost cell formed after the first division of the zygote." The embryonic apical cell can also be found in non-angiosperms. Suggest obsoleting PO:0004000 and replacing it with the new termembryonic apical cell for clarity, and using the name apical cell for the general class of apical cells described below.

Definition of apical cell from Esau: The single initial cell in an apical meristem of root or shoot. Characteristic of many lower vascular plants.

Definition of apical cell from Crum: A single cell at the tip of a stem, leaf, leaf or other structure that divides repeatedly to form new cells; also known as an apical intial.

Is apical cell more consistent with meristematic cell (A cell synthesizing protoplasm and producing new cells by division and with only a primary cell wall) or with initial cell (A meristematic cell that by division gives rise to two cells, one of which remains meristematic, while the other is added to the plant body)? Probably meristematic cell, because the apical cell can give rise to more than two cells (because it can have three or four cutting faces).

Proposed def. of apical cell: A single meristematic cell at the tip of a shoot axis apex, leaf apex, root apex, or thallus apex.

Comment: Occurs in bryophytes and some pteridophytes, where apical growth results from division of a single meristematic cell located at the tip of an apical meristem or plant organ, rather than from a population of meristematic cells located at the tip of an apical meristem. May be tetrahedral shaped, with three (in shoots) or four (in roots) cutting faces, or wedge shaped with two cutting faces (in non-vascular leaves or thalli). An apical cell is established upon the first cell division of an embryo or germination of a spore.

-note: the last sentence of the comment allows us to classify an embryonic apical cell as an apical cell.

Suggested ontology structure for the children of apical cell:

The dotted lines represent relations inferred by the reasoner.

Includes two ways of classifying: by structure and by gametophyte/sporophyte. Structural relations are asserted as is_a relations. The relations to gametophyte or sporophyte are inferred by the intersection_of terms.

New terms and definitions for apical cells

gametophytic apical cell: An apical cell that is part of a whole plant in the gametophytic phase.

Comment: Occurs in mosses and other bryophytes.

intersection_of: is_a apical cell, intersection_of: participates_in gametophytic phase

sporophytic apical cell: An apical cell that is part of a whole plant in the sporophytic phase.

Comment: Occurs in pteridophytes and the sporophyte of bryophytes.

intersection_of: is_a apical cell, intersection_of: participates_in sporophytic phase

thallus apical cell: An apical cell that is part of a thallus.

part_of thallus

root apical cell: A sporophytic apical cell that is part of a root apical meristem.

comment: Only occurs in the sporophytic phase of vascular plants.

part_of root apical meristem

shoot apical cell: An apical cell that is part of a shoot system.

comment: May occur in shoot axes or leaves of bryophytes or ferns.

part_of shoot system

gametophore apical cell: A shoot apical cell that is part of a gametophore.

comment: Occurs in the non-vascular shoot system of the gametophyte of mosses.

intersection_of: is_a shoot apical cell, intersection_of: part_of gametophore

leaf apical cell: A shoot apical cell that is part of a leaf apex.

comment: Occurs in the non-vascular leaves of bryophytes and the vascular leaves of some mosses. Only in plants where leaf growth is apical.

part_of leaf

non-vascular leaf apical cell: A leaf apical cell that is part of a leaf apex of a non-vascular leaf.

comment: Occurs in the non-vascular leaves of bryophytes, which grow by division of a single, wedge-shaped apical cell with two cutting faces.

part_of non-vasucular leaf; synonym: phyllid apical cell

vascular leaf apical cell: A leaf apical cell that is part of the leaf apex of a vascular leaf.

comment: Occurs in vascular leaves of some ferns in their sporophytic phase.

part_of vascular leaf

shoot axis apical cell: An apical cell at the tip of a shoot apical meristem.

Comment: Divides to produces leaf initial cells and other stem tissues.

part_of shoot apical meristem

gametophore axis apical cell: A shoot axis apical cell at the tip of a gametophore axis.

Comment: Occurs at the tips of the stems and branches of bryophytes.

part_of gametophore axis; synonym: cauloid apical cell, non-vascular shoot axis apical cell

vascular shoot axis apical cell: A shoot axis apical cell at the tip of a shoot apical meristem in a vascular shoot system.

Comment: Occurs in some ferns in their sporophytic phase.

part_of vascular_shoot system; synonym: fern shoot axis apical cell

Also:

embryonic apical cell (replaces PO:0004000): An apical cell that is part of an embryo and is the uppermost cell formed after the first division of the zygote.

Comment: For plants that grow via an apical cell in their sporophytic phase, the embryonic apical cell may remain meristematic throughout the plant's life.

Plant organs:

cauloid

- This is the term used for the gametophore stem or axis.

Suggest using gametophore axis as primary name, cauloid as synonym.

Proposed def'n: A shoot axis that is part of a gametophore.

Synonyms: cauloid, gametophyte axis, non-vascular shoot axis (broad, because it can also apply to the seta); participates_in gametophytic phase.

intersection_of: is_a plant axis, intersection_of: part_of gametophore

Add caulome as synonym of shoot axis

-Also suggest adding terms for gametophore stem and gametophore branch.

gametophore stem: A stem that is part of a gametophore.

is_a stem, part_of gametophore

gametophore branch: A branch that is part of a gametophore.

is_a branch, part_of gametophore

-If the intersection_of relations are asserted in the end user's version (e.g. Amigo), users will see dual parentage (is_a gametophore axis and is_a stem or branch).

perigonial bract

- The specialized phyllids surrounding the antheridia.

Ref: Bill and Nancy Malcolm (2006): Mosses and other Bryophytes, an illustrated glossary, second edition (MO definition)

A bract (PO:0009055) is defined as: A phyllome, usually different in form from the foliage leaves, subtending a reproductive structure. [source: POC:curators] Comment: Often used to refer to what is called here floral bract.

Proposed def'n: A bract that subtends an antheridium.

part_of gametophore, participates in gametophytic phase

Comment: When an antheridium occurs on a specialized lateral branch of the gametophore, all of the phyllomes on that branch are usually perigonial bracts. If an antheridium occurs on a main axis of the gametophore, usually only the terminal phyllomes are perigonial bracts.

foot

Moss Ontology definition: The base of the sporophytes in mosses

Proposed name and def.: sporophyte foot: A plant organ that is the base of a whole plant in the sporophytic phase and attaches it to the gametophore. (ref: Schofeld)

Comment: Found in bryophytes and some pteridophytes. In mosses, the foot is located below the seta. In ferns, the foot is formed from the upper hypobasal quandrant of the embryo. The sporophyte foot serves for both attachment and absorption. The outer portion of the foot is composed of absorptive transfer cells. (ref: Crum)

participates_in sporophytic phase, has_part transfer cell, only_in_taxon bryophytes (I know this isn't a clade, will have to create a pseudo-clade).

Additional organ related moss terms:

These were not requested by the Physcomitrella group, but they are related to the terms above and are commonly used to describe mosses, so we should add them now.

perichaetal bract

Proposed def'n: A bract that subtends an archegonium. part_of gametophore

Comment: When an archegonium occurs on a specialized lateral branch of the gametophore, all of the phyllomes on that branch are usually parichaetal bracts. If an archegonium occurs on a main axis of the gametophore, only the terminal phyllomes are usually parichaetal bracts. The two or three terminal-most perichaetal bracts may fuse to form a gametophytic perianth.

gametophytic perianth

Proposed def'n: A collective phyllome structure that consists of two or more of the most distal parachaetal bracts on a gametophore axis and surround the calyptra (capsule?).

Should it be surrounds the capsule, in case no calyptra is present?

-has_part parachaetal bract, part_of gametophore, disjoint_from perianth (PO:0009058)

Comment: The parachaetal bracts may fuse laterally in the gametophytic perianth. The gametophytic perianth is not the same structure as a perianth (PO:0009058) in angiosperms.

seta

-The stalk of a moss sporophyte.

Proposed def.: A plant axis that that holds up a spore capsule. participates_in sporophytic phase

Comment: Found in some bryophytes, especially mosses.

antheridiophore and archegoniophore

These are stalks that hold up the antheridia or archegonia in Marchantiales (liverworts)

Proposed definitions:

antheridiophore: A plant axis that bears two or more antheridia.

participates_in gametophytic phase

Comment: Found in Marchantiales.

archegoniophore: A plant axis that bears two or more archegonia.

participates_in gametophytic phase

Comment: Found in Marchantiales.

Will also add terms for antheridium stalk and archegonium stalk for stalks that hold up a single antheridium or archegonium. part_of antheridium or archegonium

Upcoming meetings 2011:

* ICBO 2011 Second International Conference on Biomedical Ontology July 26-30, 2011 Buffalo, New York

ICBO

LC contributed to the workshop proposal "From Fins to Limbs to Leaves: Facilitating anatomy ontology interoperability" Authors: Melissa Haendel, Chris Mungall, Alan Ruttenberg, David Osumi-Sutherland and Laurel Cooper (Accepted)

Full-Day Workshops Schedule:

July 26 9am-6pm The Ontological Representation of Adverse Events: Working with Multiple Biomedical Ontologies

July 27 8.30am-4pm Facilitating Anatomy Ontology Interoperability

July 26 6.30pm-9pm Evening Workshop: Common Logic

July 27 4pm-8pm Evening Workshop: Doctoral and Post-Doctoral Consortium

- LC will attend and represent the PO. Invite other plant people?

-BS suggested we might want to submit a short paper which could be published in longer form later- see above

*Plant Biology 2011, Aug 6-10th, Minneapolis, Minn

Plant Biology 2011

Early-bird registration ends May 13.

Gramene will be putting together a workshop again, focusing on pathways. PJ will present a PO poster.

Abstract deadlines: Your abstract must be submitted by March 11 if you want it to be considered for a minisymposium talk.

For inclusion on the program memory stick and in the program book, abstracts must be submitted by May 27.

* International Botanical Congress (IBC2011)

July 23rd-30th 2011, Melbourne, Australia

Registration is open Important dates

Symposium proposal was accepted, 'Bio-Ontologies for the Plant Sciences' under the Genetics, Genomics and Bioinformatics theme.

Dennis, Alejandra, Pankaj and Ramona are planning to attend.

Early bird registration deadline - Extended 1 March 2011 Deadline for registration by presenters 1 March 2011

See IBC 2011 Bio-Ontologies Symposium wiki page for more details