C4a
entrez
625018
canonical
uniprot
A0AAQ4VMX2
canonical
ensembl
ENSMUSG00000015451
resolver
genesymbol
C4a
resolver
genesymbol_syn
Slp
resolver
uniprot
B9EIU2
resolver
uniprot
Q6P3Y0
resolver
uniprot
V9GZG9
resolver
uniprot_entry
CO4A_MOUSE
resolver
uniprot_sec
B9EIU2
resolver
uniprot_sec
Q6P3Y0
resolver
uniprot_sec
V9GZG9
resolver
activity_regulation
ACTIVITY REGULATION: [Complement C4b-A]: Specifically inhibited by nanobody hC4Nb8, inhibiting the classical complement pathway. {ECO:0000269|PubMed:32769120}.
uniprot
proteins
amino_acid_sequence
MRLLWGLAWVFSFCASSLQKPRLLLFSPSVVNLGTPLSVGVQLLDAPPGQEVKGSVFLRNPKGGSCSPKKDFKLSSGDDFVLLSLEVPLEDVRSCGLFDLRRAPYIQLVAQSPWLRNTAFKATETQGVNLLYSSRRGHIFVQTDQPIYNPGQRVRYRVFALDQKMRPSTDFLTITVENSHGLRVLKKEIFTSTSILQDTFTIPDISEPGTWKISARFSDGLESNRSTHFEVKKYVLPNFEVKITPWKPYILMVPSNSDEIQLDIQARYIYGKPVQGVAYTRFALMDEQGKRTFLRGLETQAKLVEGRTHISISKDQFQAALDKINIGVRDLEGLRLYAATAVIESPGGEMEEAELTSWRFVSSAFSLDLSRTKRHLVPGAHFLLQALVREISGSEASNVIVKVSPTLVSGSDSQVLNVQQSTNRIGQVSISFPIPPTVTGLRLLVSAGSLYPMIARLTVQSPPSRGTGFLSIEPLDPRSPRVGDTFILNLQAVGIPAPTFSHYYYMIISRGQIMAMSREARRTVTSVSVLVDHQLAPSFYFVAYFYHQGHPVANSLLINIQPRDCEGKLQLKVVGAKEYHNGDMMKLRIQTDSKALVALGAVDTALYAVGGWSHKPLDMSKVFEVINSYNVGCGPGGGDDAPQVFQDAGLAFSDGDRLTQTREDLSCPKEKKSRQKRNVNFLKALSEKLGQYSSPDAKRCCQDGMTKLPMKRTCEQRAARVPQQACREPFLSCCKFAEDLRRNQTRSQAPLARKVRDMVNLIEEDDILVRTSFPENWLWRVEPVDSSKLLTVRLPDSMTTWEIHGVSLSKSKGLCVAKPTRVRVFRKFHLHLRLPISVRRFEQLELRPVLYNYLNDDKNVSVHVTPVEGLCMAGGGMMAQWVIVPAGSALPVAFSVVPTASTNVPLKLVAKGTLDSSDSVSKILQIEKEGAIHREEIVYNLDPLNNLGQMLEIPGSSDPNIVPEGDFSTFVKVTASEPLETLGSEEALSPGGVASLLRLPGCAEQTMIYLAPTLTASNYLDRTKQWSKLSPETKDHAVHLIQKGHVRIQQFRKKDGSFGAWLHRDSSTWLTAFVLKILSLAQEQVGNSPEKLQETASWLLAQQLGDGSFHDPCPVIHRAMQGGLVGSNETVALTAFVVIALHHGLNVFREGHAKQLKNRVEASITKANSFLGQKASAGLLGAHAAAITAYALTLTKASEDLRNVAHNSLMAMAEETGENLYWGLVLGSQDKVVLRPADPRSPTEPVPQAPALWIETTAYALLHLLLREGKGKMADKAASWLTHQGNFHGAFRSTQDTVVTLDALSAYWIASHTTEEKALKVTLSSMGRNGLKTHVLHLNNHQVKGLEEELKFSLGSTISVKVEGNSKGTLKILRTYNVLDMKNTTCQDLQIEVKVTDAVEYAWSAYEDYEDDYNMPATDDPSVPLQPVTPLQLFEGRRSRRRREAPKVAEERESRVHYTVCIWRNGKLGLSGMAIADITLLSGFHALRADLEKLTSLSDRYVSHFETDGPHVLLYFDSVPTTRECVGFGASQEVVVGLVQPASAVLYDYYSPDHKCSVFYAAPTKSQLLATLCSGDVCQCAEGKCPRLLRSLERRVEDKDGYRMRFACYYHQVEYGFTVKVLREDGRAAFRFFESKITQVLHFRTDTMASIGQTRNFLSRTSCRLRLEPNKEYLIMGMDGETSDNKGDPQYLLDSNTWIEEMPSEQMCKSTRHRAACFQLKDFLMEFSSRGCQV
uniprot
proteins
function
FUNCTION: Precursor of non-enzymatic components of the classical, lectin and GZMK complement pathways, which consist in a cascade of proteins that leads to phagocytosis and breakdown of pathogens and signaling that strengthens the adaptive immune system. {ECO:0000269|PubMed:32769120, ECO:0000269|PubMed:8133084}.; FUNCTION: [Complement C4b-A]: Non-enzymatic component of C3 and C5 convertases (By similarity). Generated following cleavage by complement proteases (C1S, MASP2 or GZMK, depending on the complement pathway), it covalently attaches to the surface of pathogens, where it acts as an opsonin that marks the surface of antigens for removal (By similarity). It then recruits the serine protease complement C2b to form the C3 and C5 convertases, which cleave and activate C3 and C5, respectively, the next components of the complement pathways (By similarity). Complement C4b-A isotype is responsible for effective binding to form amide bonds with immune aggregates or protein antigens, while complement C4b-B isotype catalyzes the transacylation of the thioester carbonyl group to form ester bonds with carbohydrate antigens (By similarity). {ECO:0000250|UniProtKB:P0C0L4}.; FUNCTION: [C4a anaphylatoxin]: Putative humoral mediator released following cleavage by complement proteases (C1S, MASP2 or GZMK, depending on the complement pathway). While it is strongly similar to anaphylatoxins, its role is unclear. Was reported to act as a mediator of local inflammatory process; however these effects were probably due to contamination with C3a and/C5a anaphylatoxins in biological assays. {ECO:0000250|UniProtKB:P0C0L4}.
uniprot
proteins
mass_dalton
192883
uniprot
proteins
post_translational_modification
PTM: Prior to secretion, the single-chain precursor is enzymatically cleaved by plasminogen (PLG) to yield non-identical chains alpha, beta and gamma (By similarity). During activation of the complement systems, the alpha chain is cleaved into C4a and C4b by different proteases depending on the complement pathway: C4b stays linked to the beta and gamma chains, while C4a is released in the plasma (By similarity). The alpha chain is cleaved by C1S to generate C4a and C4b following activation by the classical complement system (By similarity). The alpha chain is cleaved to generate C4a and C4b by MASP2 following activation by the lectin complement system (By similarity). The alpha chain is cleaved by GZMK to generate C4a and C4b following activation by the GZMK complement system (By similarity). Further degradation of C4b by C1 into the inactive fragments C4c and C4d blocks the generation of C3 convertase (By similarity). The proteolytic cleavages often are incomplete so that many structural forms can be found in plasma (By similarity). {ECO:0000250|UniProtKB:P0C0L4}.; PTM: [Complement C4b-A]: Upon activation, the internal thioester bond reacts with carbohydrate antigens on the target surface to form amide or ester bonds, leading to covalent association with the surface of pathogens. {ECO:0000250|UniProtKB:P0C0L4}.; PTM: [Complement C4b-A]: Complement C4b interacts with complement C3b via a thioester linkage. {ECO:0000250|UniProtKB:P0C0L4}.; PTM: N- and O-glycosylated. O-glycosylated with a core 1 or possibly core 8 glycan. {ECO:0000250|UniProtKB:P0C0L4}.
uniprot
proteins
pubmed
15489334
uniprot
proteins
pubmed
19468303
uniprot
proteins
pubmed
2997024
uniprot
proteins
pubmed
32769120
uniprot
proteins
pubmed
3754270
uniprot
proteins
pubmed
6208559
uniprot
proteins
pubmed
8133084
uniprot
proteins
sequence_length
1734
uniprot
proteins
subcellular_location
SUBCELLULAR LOCATION: Secreted {ECO:0000250|UniProtKB:P0C0L4}. Synapse {ECO:0000250|UniProtKB:P0C0L4}. Cell projection, axon {ECO:0000250|UniProtKB:P0C0L4}. Cell projection, dendrite {ECO:0000250|UniProtKB:P0C0L4}.; SUBCELLULAR LOCATION: [C4a anaphylatoxin]: Secreted {ECO:0000250|UniProtKB:P0C0L4}.; SUBCELLULAR LOCATION: [Complement C4b-A]: Secreted {ECO:0000250|UniProtKB:P0C0L4}. Cell surface {ECO:0000250|UniProtKB:P0C0L4}. Note=Covalently associated with the surface of pathogens: the internal thioester bond reacts with carbohydrate antigens on the target surface to form amide or ester bonds. {ECO:0000250|UniProtKB:P0C0L4}.
uniprot
proteins