P77994
Gene name |
sigA |
Protein name |
RNA polymerase sigma factor SigA |
Names |
Sigma-A |
Species |
Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826/ MSB8) |
KEGG Pathway |
tma:TM1451 |
EC number |
|
Protein Class |
RNA POLYMERASE SIGMA FACTOR RPO (PTHR30603) |
Descriptions
The σ factors are the key regulators of bacterial transcription initiation. Through direct read-out of promoter DNA sequence, they recruit the core RNA polymerase to sites of initiation, thereby dictating the RNA polymerase promoter-specificity. The group 1 σ factors, which direct the vast majority of transcription initiation during log phase growth and are essential for viability, are autoregulated by an N-terminal sequence known as σ1.1. The group 1 σ factors, which perform the bulk of transcription during exponential growth, are converted from an autoinhibited state, which cannot interact with promoter DNA, to an active form that recognizes promoter DNA upon binding to core RNAP. Biochemical and genetic studies have established that the N-terminal domain of group 1 σ factors, σ1.1, is required for autoinhibition.
Autoinhibitory domains (AIDs)
Target domain |
150-228 (Sigma 2 domain); 352-378 (Sigma 4.2 domain) |
Relief mechanism |
Partner binding |
Assay |
Deletion assay, Structural analysis, Split protein assay |
Accessory elements
No accessory elements
References
- Camarero JA et al. (2002) "Autoregulation of a bacterial sigma factor explored by using segmental isotopic labeling and NMR", Proceedings of the National Academy of Sciences of the United States of America, 99, 8536-41
- Schwartz EC et al. (2008) "A full-length group 1 bacterial sigma factor adopts a compact structure incompatible with DNA binding", Chemistry & biology, 15, 1091-103
Autoinhibited structure
Activated structure
3 structures for P77994
| Entry ID | Method | Resolution | Chain | Position | Source |
|---|---|---|---|---|---|
| 1TTY | NMR | - | A | 313-399 | PDB |
| 2K6X | NMR | - | A | 29-96 | PDB |
| AF-P77994-F1 | Predicted | AlphaFoldDB |
No variants for P77994
| Variant ID(s) | Position | Change | Description | Diseaes Association | Provenance |
|---|---|---|---|---|---|
| No variants for P77994 | |||||
No associated diseases with P77994
10 regional properties for P77994
| Type | Name | Position | InterPro Accession |
|---|---|---|---|
| domain | RNA polymerase sigma-70 | 183 - 196 | IPR000943-1 |
| domain | RNA polymerase sigma-70 | 207 - 215 | IPR000943-2 |
| domain | RNA polymerase sigma-70 | 331 - 343 | IPR000943-3 |
| domain | RNA polymerase sigma-70 | 352 - 378 | IPR000943-4 |
| domain | RNA polymerase sigma factor 70, region 1.1 | 32 - 108 | IPR007127 |
| domain | RNA polymerase sigma-70 region 3 | 238 - 313 | IPR007624 |
| domain | RNA polymerase sigma-70 region 2 | 159 - 228 | IPR007627 |
| domain | RNA polymerase sigma-70 region 4 | 327 - 380 | IPR007630 |
| domain | RNA polymerase sigma factor RpoD, C-terminal | 155 - 391 | IPR012760 |
| domain | RNA polymerase sigma-70 like domain | 155 - 380 | IPR014284 |
Functions
| Description | ||
|---|---|---|
| EC Number | ||
| Subcellular Localization |
|
|
| PANTHER Family | PTHR30603 | RNA POLYMERASE SIGMA FACTOR RPO |
| PANTHER Subfamily | PTHR30603:SF47 | RNA POLYMERASE SIGMA FACTOR SIGF, CHLOROPLASTIC |
| PANTHER Protein Class |
helix-turn-helix transcription factor
Sigma factor |
|
| PANTHER Pathway Category | No pathway information available | |
1 GO annotations of cellular component
| Name | Definition |
|---|---|
| cytoplasm | The contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures. |
2 GO annotations of molecular function
| Name | Definition |
|---|---|
| DNA binding | Any molecular function by which a gene product interacts selectively and non-covalently with DNA (deoxyribonucleic acid). |
| sigma factor activity | Sigma factors act as the promoter specificity subunit of eubacterial and plant plastid multisubunit RNA polymerases, whose core subunit composition is often described as alpha(2)-beta-beta-prime. Although sigma does not bind DNA on its own, when combined with the core to form the holoenzyme, the sigma factor binds specifically to promoter elements. The sigma subunit is released once elongation begins. |
1 GO annotations of biological process
| Name | Definition |
|---|---|
| DNA-templated transcription, initiation | The initial step of transcription, consisting of the assembly of the RNA polymerase preinitiation complex (PIC) at a gene promoter, as well as the formation of the first few bonds of the RNA transcript. Transcription initiation includes abortive initiation events, which occur when the first few nucleotides are repeatedly synthesized and then released, and ends when promoter clearance takes place. |
No homologous proteins in AiPD
| UniProt AC | Gene Name | Protein Name | Species | Evidence Code |
|---|---|---|---|---|
| No homologous proteins | ||||
| 10 | 20 | 30 | 40 | 50 | 60 |
| MNEEQQVLQE | QHQEQTQEQT | QEQKETLPPQ | IERRIKKLIS | LGKKKGYITY | EDIDKAFPPD |
| 70 | 80 | 90 | 100 | 110 | 120 |
| FEGFDTNLIE | RIHEELEKHG | INIVENEPEE | EEISASSDEQ | ELEELLEKES | PEIHDSSNVR |
| 130 | 140 | 150 | 160 | 170 | 180 |
| DSIKMYLKEI | GKIPLLTPAQ | ERELARRAQM | GDKKAKEKLI | TSNLRLVVSI | AKRYMGRGLS |
| 190 | 200 | 210 | 220 | 230 | 240 |
| FQDLIQEGNI | GLLKAVEKFD | WRKGYKFSTY | ATWWIRQAIT | RAIADQARTI | RIPVHMVETI |
| 250 | 260 | 270 | 280 | 290 | 300 |
| NKLNRLRREY | YQKHGEEPSI | EELAKMMGKP | PEKIKEILEA | AKETISLESP | IGEDEDSSIE |
| 310 | 320 | 330 | 340 | 350 | 360 |
| DFVADDSIAS | PKKEAMRMLM | REELEKVLKT | LSPREAMVLR | MRYGLLDGKP | KTLEEVGQYF |
| 370 | 380 | 390 | |||
| NVTRERIRQI | EVKALRKLRH | PSRSKYLKSL | LSLMDENEG |