>TIGR02937 sigma70-ECF RNA polymerase sigma factor, sigma-70 family; InterPro: IPR014284 The bacterial core RNA polymerase complex, which consists of five subunits, is sufficient for transcription elongation and termination but is unable to initiate transcription. Transcription initiation from promoter elements requires a sixth, dissociable subunit called a sigma factor, which reversibly associates with the core RNA polymerase complex to form a holoenzyme . RNA polymerase recruits alternative sigma factors as a means of switching on specific regulons. Most bacteria express a multiplicity of sigma factors. Two of these factors, sigma-70 (gene rpoD), generally known as the major or primary sigma factor, and sigma-54 (gene rpoN or ntrA) direct the transcription of a wide variety of genes. The other sigma factors, known as alternative sigma factors, are required for the transcription of specific subsets of genes. With regard to sequence similarity, sigma factors can be grouped into two classes, the sigma-54 and sigma-70 families. Sequence alignments of the sigma70 family members reveal four conserved regions that can be further divided into subregions eg. sub-region 2.2, which may be involved in the binding of the sigma factor to the core RNA polymerase; and sub-region 4.2, which seems to harbor a DNA-binding 'helix-turn-helix' motif involved in binding the conserved -35 region of promoters recognized by the major sigma factors , . This entry is found in all varieties of the sigma-70 type sigma factors, including the ECF subfamily. A number of sigma factors have names with a different number than 70 (i.e. sigma-38), but in fact, all except for the Sigma-54 family (IPR000394 from INTERPRO) are included within this entry. ; GO: 0003677 DNA binding, 0003700 transcription factor activity, 0016987 sigma factor activity, 0006352 transcription initiation, 0006355 regulation of transcription DNA-dependent.

Probab=99.77 E-value=1.9e-17 Score=156.68 Aligned_cols=159 Identities=23% Similarity=0.290 Sum_probs=135.7 Q ss_pred HHHHHHHHHHHHHHHHHHHHCCCCCCHHHHHHHHHHHHHHHHHHCCCCCCCEEEHHHHHHHHHHHHHHHHHCCCEEECCC Q ss_conf 68999875557899988752235677788754436799998874385457312010289899999999972287046142 Q gi|254780289|r 444 AKKEMVEANLRLVISVAKKYTNRGLQFLDLIQEGNIGLMKAAEKFDWCLGYKFSTYAMWWVKQAITRSIADQSCTIRIPV 523 (682) Q Consensus 444 AK~~l~~anlr~v~~~~~~~~~~~~~~~~~~~~~~~~l~~a~~~~~~~~g~~f~tya~~~i~~~i~~~~~~~~~~~r~~~ 523 (682) T Consensus 2 a~~~l~~~~~~~~~~~a~~~~~~~~~aeDl~Qe~~~~~~~~~~~~~~~-~~~f~~wl~~~~~n~~~d~~R~~~~~~~~~~ 80 (162) T TIGR02937 2 AFEELVERYLPLLYRYARRYLGDDADAEDLVQEAFLKLLEALDRFDPE-GGSFKAWLFRIARNLILDYLRRKRRRVRRLR 80 (162) T ss_pred HHHHHHHHHHHHHHHHHHHHHCCHHHHHHHHHHHHHHHHHHHHHCCCC-CCCHHHHHHHHHHHHHHHHHHHHHHHHHHHH T ss_conf 788999999999999999971787579999999999999878624878-7653899999999999999998664420014 Q ss_pred HHHHHHHHHHHHHHHHHHHCCCCCCHHHHHHHCCCCHHHHHHHHHHHCCCCCCCCCCCCCCCCEEEEEECCCCCCCHHHH Q ss_conf 05889899999999987760889997899987099989999999860898755363588998604756238988998999 Q gi|254780289|r 524 HMRDKIHKVVRTARRMSNKIKREPTPEEIAKKLAMPVEGVRKVLKITKEPISLETPIGDEDTSHLGDFIEDKNAVSPLDS 603 (682) Q Consensus 524 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~a~~~~~~~~~~~~~~~~~~~~~sl~~~~~~~~~~~~~~~~~d~~~~~~~~~ 603 (682) T Consensus 81 ~~~~~~-----------------------------------------------------~~-----~~~~-~-~~~~~~- 99 (162) T TIGR02937 81 VELDED-----------------------------------------------------DE-----LEEL-E-DPSPEE- 99 (162) T ss_pred HHHCCH-----------------------------------------------------HH-----HHHH-C-CCCHHH- T ss_conf 541221-----------------------------------------------------34-----4321-3-578778- Q ss_pred HHHHHHHHHHHHHHHCCCHHHHHHHHHHHCCCCCCCCCHHHHHHHHCCCHHHHHHHHHHHHHHHCC Q ss_conf 999999999999973299889999999818798674688999899667899999999999998329 Q gi|254780289|r 604 AIQANLRETTTRVLASLTPREERVLRMRFGIGMNTDHTLEEVGKQFCVTRERIRQIEAKAIRKLKH 669 (682) Q Consensus 604 ~~~~~~~~~~~~~l~~l~~re~~v~~~r~g~~~~~~~tl~e~~~~~~~~~er~rqi~~~a~~~l~~ 669 (682) T Consensus 100 ~~-~~~~~~l~~al~~Lp~~~r~~~~l~~----~~~~s~~eIA~~lg~s~~~v~~~~~ra~~~L~~ 160 (162) T TIGR02937 100 LE-EEEREALREALEKLPEREREVLVLRY----LEGLSYKEIAEILGISEGTVKSRLKRARKKLRE 160 (162) T ss_pred HH-HHHHHHHHHHHHHCCHHHHHHHHHHH----HHCCCHHHHHHHHCCCHHHHHHHHHHHHHHHHH T ss_conf 99-99999999998747998999999999----718998899998689999999999999999985

HHsearch alignment for GI: 254780289 and conserved domain: TIGR02937