EASY: myelin related terms

[gocentral]

Hi

Could I please have the following new GO terms for the annotation of P21145.

>lipid binding GO:0008289 >>glycosphingolipid binding' (GO:new) PMID:10739088

>myelin formation (GO:new) or can you suggest something? PMID:10739088

>apical membrane (GO:new) >>apical plasma membrane (GO:0016324) PMID:12153749

>membrane (GO:0016020) >>myelin membrane (GO:new) PMID:12153749

cheers Evelyn

Reported by: ecamon

Original Ticket: "geneontology/ontology-requests/1925":https://sourceforge.net/p/geneontology/ontology-requests/1925

[gocentral]

• priority: 5 --> 9

Original comment by: ecamon

[gocentral]

Logged In: YES user_id=835115

You might consider making the new term myelin membrane a (part of?) child of plasma membrane rather than just membrane. Myelin is just a specialized usage of the plasma membrane.

The GO term GO:0042552 'myelination' should cover what you were looking for with the term 'myelin formation' right? Or were you getting at the distinction between myelin formation and myelin maintenance?

-Doug

Original comment by: doughowe

[gocentral]

Logged In: YES user_id=463625

Hi Doug

I think GO:0042552 'myelination'will do the trick for that one.

cheers Evelyn

Original comment by: ecamon

[gocentral]

Logged In: YES user_id=463625

I take that back..reading PMID 12153749

'suggests an important role for MAL in the maintenance of the myelin sheath'

So need:myelin maintenance or myelin sheath maintenance may also need myelin sheath as component term please.

structural constituent of myelin sheath is function not component.

cheers Ev

Original comment by: ecamon

[gocentral]

Logged In: YES user_id=463625

More info Myelin membrane request:PMID 12153749

However, the situation might be more complicated in myelinating cells where several structurally and functionally distinct membrane compartments exist within the myelin sheath, which include compact myelin, paranodal, periaxonal and inscisural membranes. These myelin compartments are characterized by unique protein and lipid compositions (for review see, Scherer 1996, 1997; Arroyo and Scherer 2000).

Original comment by: ecamon

[gocentral]

Logged In: YES user_id=835115

For the myelin related terms in this SF item, I would suggest:

PROCESS: myelination (GO:0042552) <myelin formation (GO:NEW) <myelin maintenance (GO:NEW)

COMPONENT: plasma membrane (GO:0005886) <myelin sheath <compact myelin <paranodal myelin <periaxonal myelin <inscisural myelin

Original comment by: doughowe

[gocentral]

• milestone: --> TermGenie
• assigned_to: nobody --> jl242

Original comment by: jl242

[gocentral]

Logged In: YES user_id=451873

[from Nicolas Le Novere]

Looks fine to me, although I don't know much about myelin.

"Myelin Basic Protein" and " Proteolipid Protein" (synonymous: lipophilin) should then be linked to "myelin sheath" (part-of? or through myelin-associated proteins).

Original comment by: jl242

[gocentral]

Logged In: YES user_id=835115

Jane, I'm affraid I don't understand your last comment. Can you clarify?

When you say the two proteins should be "linked" to myelin sheath, do you mean to say they should be annotated with the proposed new GO term 'myelin sheath'? If that is what you meant, then yes they should be. These two proteins could also be annotated to one or more of the proposed children of "myelin sheath" if the publication shows that kind of detail.

-Doug -Doug

Original comment by: doughowe

[gocentral]

Logged In: YES user_id=451873

Sorry Doug - that was just a comment someone sent me - it's more to do with annotation than new terms really.

I've added the new terms:

glycosphingolipid binding ; GO:0043208 myelin sheath ; GO:0043209

I didn't add 'apical membrane' because I think it's the same as 'apical plasma membrane (GO:0016324)' - couldn't find the phrase in that reference. Does anyone know any different?

Doug - can you suggest definitions for these terms do you think:

PROCESS: <myelin formation (GO:NEW) <myelin maintenance (GO:NEW)

COMPONENT: <compact myelin <paranodal myelin <periaxonal myelin <inscisural myelin

many thanks,

Jane

Original comment by: jl242

[gocentral]

Logged In: YES user_id=835115

Defs for new terms:

Process Terms- 1) myelin formation: SYNONYM: exact synonym should be myelination. The process by which oligodendrocytes in the brain and spinal cord and Schwann cells in the peripheral nervous system wrap axons with compact layers of their plasma membrane. Adjacent myelin segments are separated by a non-myelinated stretch of axon called a node of Ranvier.

2) myelin maintenance: The process of preserving the structure and function of mature myelin. This includes maintaining the compact structure of myelin necessary for its electrical insulating characteristics as well as the structure of non-compact regions such as Schmidt-Lantermann clefts and paranodal loops. This does not include processes responsible for maintaining the nodes of Ranvier, which are not part of the myelin sheath.

Component Terms:

1) Compact myelin: The portion of the myelin sheath in which layers of cell membrane are tightly juxtaposed, completely excluding cytoplasm. The juxtaposed cytoplasmic surfaces form the major dense line, while the juxtaposed extracellular surfaces form the interperiod line visible in electron micrographs.

2) lateral loop: --I believe this is the appropriate term to use rather than 'paranodal myelin'.

Non-compact myelin located adjacent to the nodes of Ranvier in a myelin segment. These non-compact regions include cytoplasm from the cell responsible for synthesizing the myelin. Lateral loops are found in the paranodal region adjacent to the nodes of Ranvier, while Schmidt-Lantermann clefts are analogous structures found within the compact myelin internode.

3) Schmidt-Lantermann cleft: --I believe this is the appropriate term to use rather than 'incisural myelin'

Regions within compact myelin in which the cytoplasmic faces of the enveloping myelin sheath are not tightly juxtaposed, and include cytoplasm from the cell responsible for making the myelin. Schmidt-Lantermann clefts occur in the compact myelin internode, while lateral loops are analogous structures found in the paranodal region adjacent to the nodes of Ranvier.

4) periaxonal myelin: --I think we can do without this term. I think what I meant when I was thinking of this earlier is the periaxonal space...which is the space between the myelin and the axon. But I suppose this is really just extracellular space.

-Doug

Original comment by: doughowe

[gocentral]

Logged In: YES user_id=451873

Added new terms:

myelin maintenance ; GO:0043217 as child of nerve ensheathment ; GO:0008366

compact myelin ; GO:0043218 lateral loop ; GO:0043219 Schmidt-Lanterman cleft ; GO:0043220

as children of myelin sheath ; GO:0043209

with definitions suggested by Doug.

Original comment by: jl242

[gocentral]

• status: open --> closed-accepted

Original comment by: jl242

[gocentral]

• priority: 9 --> 5

Original comment by: mah11