>cd00066 G-alpha G protein alpha subunit. The alpha subunit of G proteins contains the guanine nucleotide binding site. The heterotrimeric GNP-binding proteins are signal transducers that communicate signals from many hormones, neurotransmitters, chemokines, and autocrine and paracrine factors. Extracellular signals are received by receptors, which activate the G proteins, which in turn route the signals to several distinct intracellular signaling pathways. The alpha subunit of G proteins is a weak GTPase. In the resting state, heterotrimeric G proteins are associated at the cytosolic face of the plasma membrane and the alpha subunit binds to GDP. Upon activation by a receptor GDP is replaced with GTP, and the G-alpha/GTP complex dissociates from the beta and gamma subunits. This results in activation of downstream signaling pathways, such as cAMP synthesis by adenylyl cyclase, which is terminated when GTP is hydrolized and the heterotrimers reconstitute.

Probab=97.06 E-value=0.0021 Score=40.42 Aligned_cols=130 Identities=13% Similarity=0.149 Sum_probs=77.9 Q ss_pred CEECCEEEE----ECCEEEEEECCCCCCCCCCCCCCCHHHHHHHHHHHHHHHHHCCCCCCCH--HHH--HHHHHHHHHHH Q ss_conf 000102663----2986899822642124731167751234433333578875202222110--134--66678998777 Q gi|254780648|r 194 LYPNLGIVK----EGYKEFILADIPGIIKNAHQGAGIGDRFLKHTERTHVLLHIVSALEENV--QAA--YQCILDELSAY 265 (335) Q Consensus 194 ~~P~lGvv~----~~~~~~~i~D~PGlIegA~~~~glG~~FLrhIer~~vLl~VVD~s~~d~--~~~--~~~I~~EL~~y 265 (335) T Consensus 145 R~~TtGI~e~~F~~~~~~~~~~DVGGQ---rseRkKWi~~----Fe~V~aiiFvvsLs~yDq~l~Ed~~~Nrl~eSl~LF 217 (317) T cd00066 145 RVKTTGIVETKFTIKNLKFRMFDVGGQ---RSERKKWIHC----FEDVTAIIFVVALSEYDQVLFEDESTNRMQESLNLF 217 (317) T ss_pred HCCCCCCEEEEEEECCEEEEEECCCCC---CCCCCCHHHH----HCCCCEEEEEEECCCCCCCCCCCCCHHHHHHHHHHH T ss_conf 356788316999977767998516888---4434346888----467766998852353233555664517899999999 Q ss_pred H-----HHHCCCCEEEEEECCCCCCHHH------------------HHHH----HHHHHHHC---CCC--EEEEECCCCC Q ss_conf 6-----6750598899997465899889------------------9999----99999862---994--8999888788 Q gi|254780648|r 266 N-----SELRKKIEIVGLSQIDTVDSDT------------------LARK----KNELATQC---GQV--PFEFSSITGH 313 (335) Q Consensus 266 ~-----~~L~~Kp~IIVlNKiDl~~~e~------------------~~~~----~~~l~~~~---~~~--vi~ISA~tg~ 313 (335) T Consensus 218 ~~i~n~~~f~~~~iiLflNK~Dlf~eKi~~~~l~~~Fpdy~g~~~~~~~a~~fi~~kF~~~~~~~~r~~y~h~T~A~Dt~ 297 (317) T cd00066 218 DSICNSRWFANTSIILFLNKKDLFEEKIKKSPLTDYFPDYTGPPNDYEEAAKFIRKKFLDLNRNPNKEIYPHFTCATDTE 297 (317) T ss_pred HHHHCCHHHCCCCEEEEEECHHHHHHHCCCCCHHHCCCCCCCCCCCHHHHHHHHHHHHHHHCCCCCCCEEEEECCEECHH T ss_conf 99974874557988999857699998647995442288999999999999999999999853689985778756110528 Q ss_pred CHHHHHHHHHHHHHHHH Q ss_conf 99999999999998545 Q gi|254780648|r 314 GIPQILECLHDKIFSIR 330 (335) Q Consensus 314 GI~eL~~~I~e~L~~~r 330 (335) T Consensus 298 ~i~~vf~~v~d~I~~~~ 314 (317) T cd00066 298 NIRFVFDAVKDIILQNN 314 (317) T ss_pred HHHHHHHHHHHHHHHHH T ss_conf 99999999999999987

HHsearch alignment for GI: 254780648 and conserved domain: cd00066