Phage Hunters Spring 2017
My Annotations
| Status | Page | Date/Time | GO Term (Aspect) | Reference | Evidence | Notes | Links |
|---|
| acceptable | BPHK0:VNUN | 2017-04-06 22:50:49 CDT | GO:0006353 DNA-templated transcription, termination (P) | PMID:7714899 | ECO:0000314 direct assay evidence used in manual assertion | Figure 2 - In an in vitro system with RNA polymerase and the nun protein, increasing concentration of nun correlated with increasing amounts of relatively shorter RNA transcripts.
(Data not shown) - Adding the nun protein after completion of transcription did not shorten RNA transcripts. Thus, its unlikely nun acts by cleaving or processing RNA transcripts.
Figure 3A - Without nun, RNA polymerase transcription would only pause at certain lengths of RNA, before resuming activity again. However in presence of nun, transcription would completely be completely blocked without resuming again once these similar length RNA transcripts were reached. Both with and without nun, similar length RNA transcripts would appear at similar times.
Figure 3B - Next, the authors separated the the RNA transcript products onto a gel. They found that the sites that nun acted on and the sites where RNA polymerase paused were either identical or extremely close in proximity. All these results taken into consideration suggest nun arrests transcription by directly acting at RNA polymerase pause sites.
| challenge |
| updatedbyinstructor | 9CAUD:U5PXE3 | 2017-04-12 09:12:18 CDT | GO:0006352 DNA-templated transcription, initiation (P) | GO_REF:0000100 | ECO:0000250 sequence similarity evidence used in manual assertion | HHpred top two matches as: RNA polymerase sigma factor CnrH (P37978) from Cupriavidus metallidurans - probability: 99.77 e-value: 1.1E-20 score: 139.19 Query coverage: 27-211 (out of 1-211). This protein has a previous annotation for DNA template transcription initiation shown through IDA. There were many Blastp matches with 100% or near 100% query coverage and low e-values to purported putative sigma factors on recently annotated phages.
PMID:16158236 - showing function for CnrH from Cupriavidus metallidurans
A sigma factor's likely role in a phage is to modulate gene expression to its own promoters, while downregulating transcription of host genes.
| challenge |
acceptable:1
unacceptable:0
requires_changes:0
flagged:0
Annotations challenged by Zhm1
| Status | Author,Group | Page | GO Term (Aspect) | Reference | Evidence | Links | Page history |
|---|
0 annotations fixed by Zhm1
What do the icons mean in the status column?
