>TIGR01425 SRP54_euk signal recognition particle protein SRP54; InterPro: IPR006325 The signal recognition particle (SRP) is a multimeric protein, which along with its conjugate receptor (SR), is involved in targeting secretory proteins to the rough endoplasmic reticulum (RER) membrane in eukaryotes, or to the plasma membrane in prokaryotes , . SRP recognises the signal sequence of the nascent polypeptide on the ribosome, retards its elongation, and docks the SRP-ribosome-polypeptide complex to the RER membrane via the SR receptor. SRP consists of six polypeptides (SRP9, SRP14, SRP19, SRP54, SRP68 and SRP72) and a single 300 nucleotide 7S RNA molecule. The RNA component catalyses the interaction of SRP with its SR receptor . In higher eukaryotes, the SRP complex consists of the Alu domain and the S domain linked by the SRP RNA. The Alu domain consists of a heterodimer of SRP9 and SRP14 bound to the 5' and 3' terminal sequences of SRP RNA. This domain is necessary for retarding the elongation of the nascent polypeptide chain, which gives SRP time to dock the ribosome-polypeptide complex to the RER membrane. This entry represents the 54 kDa SRP54 component, a GTP-binding protein that interacts with the signal sequence when it emerges from the ribosome. SRP54 of the signal recognition particle has a three-domain structure: an N-terminal helical bundle domain, a GTPase domain, and the M-domain that binds the 7s RNA and also binds the signal sequence. The extreme C-terminal region is glycine-rich and lower in complexity and poorly conserved between species.; GO: 0005525 GTP binding, 0008312 7S RNA binding, 0006614 SRP-dependent cotranslational protein targeting to membrane, 0048500 signal recognition particle.

Probab=97.12 E-value=0.00074 Score=45.92 Aligned_cols=221 Identities=19% Similarity=0.263 Sum_probs=130.0 Q ss_pred HHH-CCCCCCCCHHHHHHHHCCCCCCCHHHHH-----------HHHHHHHHHHHHHHHH--HHHHHHHHHHHHCCC--CC Q ss_conf 731-4799988989999874488846899999-----------9989999999999999--999899999871677--66 Q gi|254780827|r 16 AVH-SKFSSILSKKISNQLLSFDSPIDSTEIY-----------KIYFPLSHLLLINVNS--AKITCHQYNKFLNLK--EE 79 (311) Q Consensus 16 ~~~-~~~~~~l~~~~~~~l~~~~d~i~~~ev~-----------~iy~pl~~ll~~~~~~--~~~~~~~~~~fl~~~--~~ 79 (311) T Consensus 38 ALL~~dvn~klv~~l~~Nik~kid~~n~e~~~~g~nKRk~iq~~vF~EL~~LvDp~~~APkPkklststktinGkk~~p~ 117 (453) T TIGR01425 38 ALLESDVNVKLVRQLRENIKKKIDKINLEELASGLNKRKLIQKAVFEELCNLVDPGVEAPKPKKLSTSTKTINGKKFTPK 117 (453) T ss_pred HHHHCCCCHHHHHHHHHHHHHHCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHCCCCCCCCCCCCCCCCCEEECCCEEECC T ss_conf 75113352677898888788740503513321032478999998999989760863234687533321101035034115 Q ss_pred CCCCEEEEEECCCCCCHHHHHHHHHHHHHHCCCCCEEEEEECCCCCCHHHHHHHCHHHCCCCHHHHHHHHHHHHHHHHHC Q ss_conf 78767999527866673379999999997338986899950887588268876000201898133128999999997412 Q gi|254780827|r 80 SKIPFVVGITGSVAVGKSTFARILCILLQQISNFKVSLITTDGFLFPNAVLTANNLMQRKGFPESYDSNKLLTFLSDVKS 159 (311) Q Consensus 80 ~k~PfIIGIAG~~asGKST~Ar~L~~lL~~~~~~~V~lis~DgF~~~n~~l~~~~l~~rkGfPeS~D~~~L~~~L~~lK~ 159 (311) T Consensus 118 Kgk~~ViMfVGLQGaGKTTtctKLA~YYk~-rGfK~~lvCADTF-R-------------AG---AFd---------QLkq 170 (453) T TIGR01425 118 KGKSSVIMFVGLQGAGKTTTCTKLAYYYKR-RGFKPALVCADTF-R-------------AG---AFD---------QLKQ 170 (453) T ss_pred CCCCEEEEEEECCCCCHHHHHHHHHHHHHC-CCCCEEEECCCCC-C-------------CC---HHH---------HHHH T ss_conf 688215888621488715668787777632-6643256517754-2-------------32---489---------9987 Q ss_pred CCCEEEEECCCCCCCCCCCCCEEEECCCCEEEEECCHHCCCCCCCCCCCCCEEECCCCCEEEEEECCHHHHHHHHHHHHH Q ss_conf 66405874044322565898369986896599706100357654575777401000231157730889998879988788 Q gi|254780827|r 160 GKKKVAVPRYSHSQYDILEGEYDTIIQPDILLIEGINVLQQNSLSDNQKATPMISDFLDFSIYIDADKRDIHRWYLNRFL 239 (311) Q Consensus 160 G~~~V~~PvYsh~~~D~vp~~~~vi~~pdIIIvEGi~vL~~~~l~~~~~~~~~vsD~fD~sIyVDad~~~i~~wyi~Rf~ 239 (311) T Consensus 171 NA~kA~iPFY---------Gsy~E~DP-VkiA~EGv~~Fk~E--------------~~d-iIivDTSGRHkQe~~LF~Em 225 (453) T TIGR01425 171 NATKAKIPFY---------GSYLESDP-VKIASEGVEKFKKE--------------KFD-IIIVDTSGRHKQEEELFEEM 225 (453) T ss_pred HHHHCCCCCC---------CCCCCCCC-EEEECCCHHHHHCC--------------CCC-EEEEECCCCCHHHHHHHHHH T ss_conf 4764489712---------01048987-07800201132212--------------784-79983798732258888998 Q ss_pred HHHHHHCCCHHHHHHHHHCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCEEEEECCCCCC Q ss_conf 876652016777998860599899999999998863166899952013136649997589984 Q gi|254780827|r 240 KLRETAFLNPRSYFHHFTEISEEQSLKIAETAWNNINLPNLQHNILPTRKRADLILSKGEDHS 302 (311) Q Consensus 240 ~lr~~a~~~~~s~~~~y~~l~~~ea~~~a~~iW~~in~pnl~e~I~PTr~rADlIi~k~~~H~ 302 (311) T Consensus 226 ~qv~~A-i~Pd~iifVMDGsIGQAA~~QA---------kAFK~----~~~vGSvIiTKLDGHA 274 (453) T TIGR01425 226 VQVAEA-IKPDSIIFVMDGSIGQAAFSQA---------KAFKD----SVEVGSVIITKLDGHA 274 (453) T ss_pred HHHHHC-CCCCCEEEEECCCHHHHHHHHH---------HHHHH----CCCCEEEEEECCCCCC T ss_conf 768633-4998369980661667889999---------98630----0350038875156776

HHsearch alignment for GI: 254780827 and conserved domain: TIGR01425