[Ontology-editors] forward and reverse transcription

[Harold Drabkin]

It's all in what the copy is used for I think:

I suppose an RNA dependent RNA polymerase  vs a DNA dependent RNA 
polymerase... vs ....

In the case of some single strand viral genomes:

A negative-sense ssRNA virus  genome is copied by  an RNA polymerase to 
form positive-sense RNA. This means that the virus must bring along with 
it the RNA-dependent RNA polymerase enzyme. The positive-sense RNA 
molecule then acts as viral mRNA, which is translated into proteins by 
the host ribosomes.

A positive-sense ssRNA viruse genome is directly used as an mRNA, making 
a single protein which is modified by host and viral proteins to form 
the various proteins needed for replication. One of these includes 
RNA-dependent RNA polymerase, which copies the viral RNA to form a 
double-stranded replicative form, in turn this directs the formation of 
new virions.

Both processes use an RNA template and make an RNA. one is 
transcription, the other replication.

hjd

Midori Harris wrote:
> Wait, I'm confused now about what you guys favor. RNA-dependent 
> synthesis of RNA isn't transcription at all; it's RNA replication.
>
> Transcription is the interconversion of DNA and RNA by synthesizing 
> one on a template made of the other. Synthesis of RNA on a DNA 
> template is considered "forward" because it's by far the more common 
> direction.
>
> m
>
> On Mon, 1 Dec 2008, David Hill wrote:
>
>> I agree with Harold.  Reverse transcription refers to the process of 
>> reversing the transcription process, not a type of transcription.
>>
>> Harold Drabkin wrote:
>>> Hmm, from  the def of 64101, the term name really doesn't fit, since 
>>> to me, RNA -dependent transcription would be a process whereby an 
>>> RNA template is transcribed to create another RNA molecule. As it's 
>>> defined, it is "reverse" transcription.
>>> Based on the def, I would vote to merge them.
>>> Posted to SF also
>>>
>>>
>>> Midori Harris wrote:
>>>> Hi,
>>>>
>>>> A couple of questions have come up in SF 2354289:
>>>>
>>>> 1. Should these terms be merged?
>>>>
>>>>   id: GO:0006278
>>>>   name: RNA-dependent DNA replication
>>>>   def: "The process whereby new strands of DNA are synthesized, 
>>>> using RNA
>>>>   as a template for RNA-dependent DNA polymerases (e.g. reverse
>>>>   transcriptase) that synthesize the new strands."
>>>>
>>>>   id: GO:0006410
>>>>   name: transcription, RNA-dependent
>>>>   namespace: biological_process
>>>>   def: "The synthesis of DNA on a template of RNA."
>>>>
>>>> 2. Should reverse transcription be considered part of gene 
>>>> expression (at present it is, by transitivity, but if it shouldn't 
>>>> be, it's easy to change)?
>>>>
>>>> Comments here or on the SF item much appreciated.
>>>>
>>>> https://sourceforge.net/tracker/index.php?func=detail&aid=2354289&group_id=36855&atid=440764 
>>>>
>>>> Midori