ID KAIB_SYNP7 STANDARD; PRT; 102 AA. AC Q79PF5; Q9Z3H3; DT 11-OCT-2004, integrated into UniProtKB/Swiss-Prot. DT 05-JUL-2004, sequence version 1. DT 07-MAR-2006, entry version 13. DE Circadian clock protein kaiB. GN Name=kaiB; ORFNames=see0010; OS Synechococcus sp. (strain PCC 7942) (Anacystis nidulans R2). OC Bacteria; Cyanobacteria; Chroococcales; Synechococcus. OX NCBI_TaxID=1140; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA], FUNCTION, AND MUTANTS KAIB1 AND RP KAIB2. RX MEDLINE=98397326; PubMed=9727980; DOI=10.1126/science.281.5382.1519; RA Ishiura M., Kutsuna S., Aoki S., Iwasaki H., Andersson C.R., RA Tanabe A., Golden S.S., Johnson C.H., Kondo T.; RT "Expression of a gene cluster kaiABC as a circadian feedback process RT in cyanobacteria."; RL Science 281:1519-1523(1998). RN [2] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RA Holtman C.K., Sandoval P., Chen Y., Socias T., Mohler B.J., RA McMurtry S., Gonzalez A., Salinas I., Golden S.S., Youderian P.; RT "Synechococcus elongatus PCC7942 cosmid 7G3."; RL Submitted (JUN-2002) to the EMBL/GenBank/DDBJ databases. RN [3] RP HOMODIMERIZATION, AND INTERACTIONS WITH KAIA AND KAIC. RX PubMed=10064581; DOI=10.1093/emboj/18.5.1137; RA Iwasaki H., Taniguchi Y., Ishiura M., Kondo T.; RT "Physical interactions among circadian clock proteins KaiA, KaiB and RT KaiC in cyanobacteria."; RL EMBO J. 18:1137-1145(1999). RN [4] RP FUNCTION, AND INTERACTION WITH KAIC. RX PubMed=12727878; DOI=10.1093/emboj/cdg168; RA Xu Y., Mori T., Johnson C.H.; RT "Cyanobacterial circadian clockwork: roles of KaiA, KaiB and the kaiBC RT promoter in regulating KaiC."; RL EMBO J. 22:2117-2126(2003). RN [5] RP FUNCTION, DEVELOPMENTAL STAGE, SUBCELLULAR LOCATION, AND INTERACTION RP WITH KAIC. RX PubMed=12727879; DOI=10.1093/emboj/cdg212; RA Kitayama Y., Iwasaki H., Nishiwaki T., Kondo T.; RT "KaiB functions as an attenuator of KaiC phosphorylation in the RT cyanobacterial circadian clock system."; RL EMBO J. 22:2127-2134(2003). RN [6] RP FUNCTION OF THE KAIABC COMPLEX, AND INDUCTION. RX PubMed=14709675; DOI=10.1073/pnas.0307411100; RA Nakahira Y., Katayama M., Miyashita H., Kutsuna S., Iwasaki H., RA Oyama T., Kondo T.; RT "Global gene repression by KaiC as a master process of prokaryotic RT circadian system."; RL Proc. Natl. Acad. Sci. U.S.A. 101:881-885(2004). CC -!- FUNCTION: Component of the kaiABC clock protein complex, which CC constitutes the main circadian regulator in cyanobacteria. The CC kaiABC complex may act as a promoter-nonspecific transcription CC regulator that represses transcription, possibly by acting on the CC state of chromosome compaction. In the complex, it decreases the CC phosphorylation status of kaiC. It has no effect on kaiC by CC itself, but instead need the presence of both kaiA and kaiC, CC suggesting that it acts by antagonizing the interaction between CC kaiA and kaiC. CC -!- SUBUNIT: Homodimer. Component of the kaiABC complex, at least CC composed of a kaiC homohexamer, a kaiB dimer and two kaiA dimers. CC The kaiABC complex also interacts with sasA. CC -!- SUBCELLULAR LOCATION: Cytoplasm. Membrane; peripheral membrane CC protein. From circadian time (CT) 12-16 to CT 20 the major CC fraction is membrane-associated, it then translocated to the CC cytosol, where it probably interacts with kaiC and kaiA. CC -!- DEVELOPMENTAL STAGE: Accumulates in a circadian fashion, peaking CC at CT 15-18. CC -!- INDUCTION: Down-regulated by kaiC. CC -!- MISCELLANEOUS: 'Kai' means 'cycle' in Japanese. CC -!- SIMILARITY: Belongs to the kaiB family. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; AB010691; BAA37102.1; -; Genomic_DNA. DR EMBL; AY120853; AAM82685.1; -; Genomic_DNA. DR PIR; T44268; T44268. DR SMR; Q79PF5; 1-98. DR HAMAP; MF_01835; -; 1. DR InterPro; IPR011649; KaiB. DR Pfam; PF07689; KaiB; 1. KW Biological rhythms; Membrane. FT CHAIN 1 102 Circadian clock protein kaiB. FT /FTId=PRO_0000217767. FT MUTAGEN 11 11 L->F: In kaiB1; shortens the period of FT the circadian rhythm to 21 hours. FT MUTAGEN 74 74 R->W: In kaiB2; shortens the period of FT the circadian rhythm to 22 hours. SQ SEQUENCE 102 AA; 11436 MW; 4E7FD086742A398F CRC64; MSPRKTYILK LYVAGNTPNS VRALKTLKNI LEVEFQGVYA LKVIDVLKNP QLAEEDKILA TPTLAKVLPL PVRRIIGDLS DREKVLIGLD LLYGELQDSD DF //