ID   SNRPA_XENLA             Reviewed;         282 AA.
AC   P45429;
DT   01-NOV-1995, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1995, sequence version 1.
DT   03-AUG-2022, entry version 96.
DE   RecName: Full=U1 small nuclear ribonucleoprotein A;
DE            Short=U1 snRNP A;
DE            Short=U1-A;
DE            Short=U1A;
GN   Name=snrpa;
OS   Xenopus laevis (African clawed frog).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Amphibia;
OC   Batrachia; Anura; Pipoidea; Pipidae; Xenopodinae; Xenopus; Xenopus.
OX   NCBI_TaxID=8355;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RX   PubMed=1829114; DOI=10.1016/0022-2836(91)90651-l;
RA   Scherly D., Kambach C., Boelens W., van Venrooij W.J., Mattaj I.W.;
RT   "Conserved amino acid residues within and outside of the N-terminal
RT   ribonucleoprotein motif of U1A small nuclear ribonucleoprotein involved in
RT   U1 RNA binding.";
RL   J. Mol. Biol. 219:577-584(1991).
CC   -!- FUNCTION: Component of the spliceosomal U1 snRNP, which is essential
CC       for recognition of the pre-mRNA 5' splice-site and the subsequent
CC       assembly of the spliceosome. U1 snRNP is the first snRNP to interact
CC       with pre-mRNA. This interaction is required for the subsequent binding
CC       of U2 snRNP and the U4/U6/U5 tri-snRNP. Snrpa binds stem loop II of U1
CC       snRNA (By similarity). {ECO:0000250}.
CC   -!- SUBUNIT: U1 snRNP is composed of the 7 core Sm proteins snrpb, snrpd1,
CC       snrpd2, snrpd3, snrpe, snrpf and snrpg that assemble in a heptameric
CC       protein ring on the Sm site of the small nuclear RNA to form the core
CC       snRNP, and at least three U1 snRNP-specific proteins snrnp70/U1-70K,
CC       snrpa/U1-A and snrpc/U1-C. {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Nucleus.
CC   -!- SIMILARITY: Belongs to the RRM U1 A/B'' family. {ECO:0000305}.
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DR   EMBL; X57953; CAA41021.1; -; mRNA.
DR   PIR; S30564; S30564.
DR   AlphaFoldDB; P45429; -.
DR   SMR; P45429; -.
DR   PRIDE; P45429; -.
DR   Proteomes; UP000186698; Genome assembly.
DR   GO; GO:0005681; C:spliceosomal complex; IEA:UniProtKB-KW.
DR   GO; GO:0005685; C:U1 snRNP; ISS:UniProtKB.
DR   GO; GO:0030619; F:U1 snRNA binding; ISS:UniProtKB.
DR   GO; GO:0006397; P:mRNA processing; IEA:UniProtKB-KW.
DR   GO; GO:0008380; P:RNA splicing; IEA:UniProtKB-KW.
DR   CDD; cd12477; RRM1_U1A; 1.
DR   CDD; cd12480; RRM2_U1A; 1.
DR   Gene3D; 3.30.70.330; -; 2.
DR   InterPro; IPR012677; Nucleotide-bd_a/b_plait_sf.
DR   InterPro; IPR035979; RBD_domain_sf.
DR   InterPro; IPR000504; RRM_dom.
DR   InterPro; IPR034407; U1A_RRM1.
DR   InterPro; IPR034409; U1A_RRM2.
DR   Pfam; PF00076; RRM_1; 2.
DR   SMART; SM00360; RRM; 2.
DR   SUPFAM; SSF54928; SSF54928; 1.
DR   PROSITE; PS50102; RRM; 2.
PE   2: Evidence at transcript level;
KW   mRNA processing; mRNA splicing; Nucleus; Reference proteome; Repeat;
KW   Ribonucleoprotein; RNA-binding; Spliceosome.
FT   CHAIN           1..282
FT                   /note="U1 small nuclear ribonucleoprotein A"
FT                   /id="PRO_0000081889"
FT   DOMAIN          10..89
FT                   /note="RRM 1"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00176"
FT   DOMAIN          208..282
FT                   /note="RRM 2"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00176"
SQ   SEQUENCE   282 AA;  31610 MW;  99C2B871C8A63F6B CRC64;
     MSIQEVRPNN TIYINNLNEK IKKDELKKSL YAIFSQFGQI LDILVSRNLK MRGQAFVIFK
     ETSSATNALR SMQGFPFYDK PMRIQYSKTD SDIIAKMKGT FVERDRKRQE KRKVKVPEVQ
     GVKNAMPGAA LLPGVPGQMA AMQDMPGMTQ APRMMHMAGQ APYMHHPGMM PPPGMAPGQM
     PPGGMPHGQL MPGQMAPMQP ISENPPNHIL FLTNLPEETN ELMLSMLFNQ FPGFKEVRLV
     PGRHDIAFVE FDNEVQAGAA RESLQGFKIT QSNSMKISFA KK