Q9EZJ8

EV
Gene name
sigA
Protein name
RNA polymerase sigma factor SigA
Names
Species
Thermus aquaticus
KEGG Pathway
EC number
Protein Class
RNA POLYMERASE SIGMA FACTOR RPO (PTHR30603)

Descriptions

The DNA-dependent RNA polymerase (RNAP) is the principal enzyme of the transcription process, and is a final target in many regulatory pathways that control gene expression in all living organisms. In bacteria, RNAP is responsible for the synthesis of all RNAs in the cell (messenger RNA, ribosomal RNA, transfer RNA, and so on).
The binding of initiation factor σ to a RNAP core enzyme results in the formation of a holoenzyme, the active form of RNAP essential for transcription initiation. The atomic model of the σ70 subunit lacks the disordered N-terminal domain (σ1-73), which includes the conserved σ region 1.1. In the autoinhibited state, the polar surface of the region 2.2 helix is partially occluded by a loop within the nonconserved insert between regions 1.2 and 2.1, which masks the DNA-binding regions of σ before it binds the core. In the complex of σ with core RNAP, the loop is repositioned to expose the core RNAP binding determinants in region 2.2.

Autoinhibitory domains (AIDs)

129-201 (Flexible loop) EV

Target domain

202-271 (σ2 domain)

Relief mechanism

Ligand binding

Assay

Structural analysis

Accessory elements

No accessory elements

References

Autoinhibited structure

Activated structure

19 structures for Q9EZJ8

Entry ID Method Resolution Chain Position Source
1KU2 X-ray 290 A A/B 92-332 PDB
1KU3 X-ray 180 A A 366-438 PDB
1KU7 X-ray 240 A A/D 366-438 PDB
1L9U X-ray 400 A H/Q 92-438 PDB
1L9Z X-ray 650 A H 1-438 PDB
1RIO X-ray 230 A H 366-438 PDB
3LES X-ray 277 A A/B 93-271 PDB
3LEV X-ray 250 A A 93-271 PDB
3N97 X-ray 325 A A/D 366-438 PDB
3UGO X-ray 210 A A 92-332 PDB
3UGP X-ray 270 A A 92-332 PDB
4KI2 X-ray 361 A A/B 92-332 PDB
4XLN X-ray 400 A F/L 92-438 PDB
4XLP X-ray 400 A F/L 92-438 PDB
4XLQ X-ray 460 A F/L 92-438 PDB
4XLR X-ray 430 A F/L 92-438 PDB
4XLS X-ray 401 A F/L 92-438 PDB
5TJG X-ray 260 A F 92-438 PDB
AF-Q9EZJ8-F1 Predicted AlphaFoldDB

No variants for Q9EZJ8

Variant ID(s) Position Change Description Diseaes Association Provenance
No variants for Q9EZJ8

No associated diseases with Q9EZJ8

10 regional properties for Q9EZJ8

Type Name Position InterPro Accession
domain RNA polymerase sigma-70 226 - 239 IPR000943-1
domain RNA polymerase sigma-70 250 - 258 IPR000943-2
domain RNA polymerase sigma-70 376 - 388 IPR000943-3
domain RNA polymerase sigma-70 397 - 423 IPR000943-4
domain RNA polymerase sigma-70 region 3 281 - 359 IPR007624
domain RNA polymerase sigma-70 region 2 202 - 271 IPR007627
domain RNA polymerase sigma-70 region 4 372 - 424 IPR007630
domain RNA polymerase sigma-70 region 1.2 94 - 127 IPR009042
domain RNA polymerase sigma factor RpoD, C-terminal 198 - 437 IPR012760
domain RNA polymerase sigma-70 like domain 198 - 424 IPR014284

Functions

Description
EC Number
Subcellular Localization
  • Cytoplasm
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
MKKSKSKKKA AKAQEVEVKE PVKEPEPLPE LEAAEDLQDL PEPDPELLAS EPELEDLADP
70 80 90 100 110 120
LDLEGPLEAD LLPEEGLLEE EEEELSLPKV STSDPVRQYL HEIGQVPLLT LEEEIDLARK
130 140 150 160 170 180
VEEGMEAIKK LSEATGLDQE LIREVVRAKI LGTARIQKIP GLKEKPDPKT VEEVDGKLKS
190 200 210 220 230 240
LPKELKRYLH IAREGEAARQ HLIEANLRLV VSIAKKYTGR GLSFLDLIQE GNQGLIRAVE
250 260 270 280 290 300
KFEYKRRFKF STYATWWIRQ AINRAIADQA RTIRIPVHMV ETINKLSRTA RQLQQELGRE
310 320 330 340 350 360
PSYEEIAEAM GPGWDAKRVE ETLKIAQEPV SLETPIGDEK DSFYGDFIPD ENLPSPVEAA
370 380 390 400 410 420
AQSLLSEELE KALSKLSERE AMVLKLRKGL IDGREHTLEE VGAYFGVTRE RIRQIENKAL
430
RKLKYHESRT RKLRDFLE