ID   MBP_SQUAC               Reviewed;         155 AA.
AC   Q91439;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   14-OCT-2008, sequence version 4.
DT   25-MAY-2022, entry version 68.
DE   RecName: Full=Myelin basic protein;
DE            Short=MBP;
GN   Name=MBP;
OS   Squalus acanthias (Spiny dogfish).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Chondrichthyes;
OC   Elasmobranchii; Squalomorphii; Squaliformes; Squalidae; Squalus.
OX   NCBI_TaxID=7797;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Brain, and Spinal cord;
RX   PubMed=7692075; DOI=10.1002/jnr.490350602;
RA   Spivack W.D., Zhong N., Salerno S., Saavedra R.A., Gould R.M.;
RT   "Molecular cloning of the myelin basic proteins in the shark, Squalus
RT   acanthias, and the ray, Raja erinacia.";
RL   J. Neurosci. Res. 35:577-584(1993).
RN   [2]
RP   SEQUENCE REVISION TO 31.
RA   Gould R.M.;
RL   Submitted (SEP-2008) to UniProtKB.
RN   [3]
RP   CLEAVAGE OF INITIATOR METHIONINE, ACETYLATION AT ALA-2, PHOSPHORYLATION AT
RP   SER-73; SER-84; SER-121; SER-122; SER-135; SER-139 AND SER-140, DEAMIDATION
RP   AT GLN-12, HYDROXYLATION, CITRULLINATION, AND IDENTIFICATION BY MASS
RP   SPECTROMETRY.
RX   PubMed=11513482; DOI=10.1023/a:1010921230859;
RA   Zand R., Jin X., Kim J., Wall D.B., Gould R., Lubman D.M.;
RT   "Studies of posttranslational modifications in spiny dogfish myelin basic
RT   protein.";
RL   Neurochem. Res. 26:539-547(2001).
CC   -!- FUNCTION: This protein may function to maintain proper structure of
CC       myelin.
CC   -!- SUBCELLULAR LOCATION: Myelin membrane; Peripheral membrane protein;
CC       Cytoplasmic side. Note=Cytoplasmic side of myelin.
CC   -!- PTM: Several charge isomers are produced as a result of optional post-
CC       translational modifications, such as phosphorylation, deamidation and
CC       citrullination. Dogfish MBP contains four major components designated
CC       as C1, C2, C3 and C8. C1 and C3, but not C2 are phosphorylated at
CC       either Ser-121 or Ser-122; C2 is phosphorylated at 2 or 3 sites among
CC       Ser-135, Ser-139 and Ser-140. Hydroxyproline and citrulline are present
CC       but were not identified in either C1, C2 or C3, which suggests their
CC       presence in C8. {ECO:0000269|PubMed:11513482}.
CC   -!- SIMILARITY: Belongs to the myelin basic protein family. {ECO:0000305}.
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; U44052; AAA96757.1; -; mRNA.
DR   AlphaFoldDB; Q91439; -.
DR   SMR; Q91439; -.
DR   iPTMnet; Q91439; -.
DR   GO; GO:0043209; C:myelin sheath; IEA:UniProtKB-SubCell.
DR   GO; GO:0005886; C:plasma membrane; IEA:UniProtKB-KW.
DR   GO; GO:0019911; F:structural constituent of myelin sheath; IEA:InterPro.
DR   InterPro; IPR000548; Myelin_BP.
DR   PANTHER; PTHR11429; PTHR11429; 1.
DR   Pfam; PF01669; Myelin_MBP; 1.
DR   PRINTS; PR00212; MYELINMBP.
DR   PROSITE; PS00569; MYELIN_MBP; 1.
PE   1: Evidence at protein level;
KW   Acetylation; Cell membrane; Citrullination; Hydroxylation; Membrane;
KW   Phosphoprotein.
FT   INIT_MET        1
FT                   /note="Removed"
FT                   /evidence="ECO:0000269|PubMed:11513482"
FT   CHAIN           2..155
FT                   /note="Myelin basic protein"
FT                   /id="PRO_0000159001"
FT   REGION          1..72
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   REGION          113..155
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   MOD_RES         2
FT                   /note="N-acetylalanine; in forms C1, C2, C3 and C8"
FT                   /evidence="ECO:0000269|PubMed:11513482"
FT   MOD_RES         12
FT                   /note="Deamidated glutamine; in forms C1, C2 and C3"
FT                   /evidence="ECO:0000269|PubMed:11513482"
FT   MOD_RES         73
FT                   /note="Phosphoserine; in forms C1, C2 and C3"
FT                   /evidence="ECO:0000269|PubMed:11513482"
FT   MOD_RES         84
FT                   /note="Phosphoserine; in forms C1, C2 and C3"
FT                   /evidence="ECO:0000269|PubMed:11513482"
FT   MOD_RES         121
FT                   /note="Phosphoserine; in forms C1 and C3"
FT                   /evidence="ECO:0000305|PubMed:11513482"
FT   MOD_RES         122
FT                   /note="Phosphoserine; in forms C1 and C3"
FT                   /evidence="ECO:0000305|PubMed:11513482"
FT   MOD_RES         135
FT                   /note="Phosphoserine; in forms C1, C2 and C3"
FT                   /evidence="ECO:0000269|PubMed:11513482"
FT   MOD_RES         139
FT                   /note="Phosphoserine; in forms C1, C2 and C3"
FT                   /evidence="ECO:0000269|PubMed:11513482"
FT   MOD_RES         140
FT                   /note="Phosphoserine; in forms C1, C2 and C3"
FT                   /evidence="ECO:0000269|PubMed:11513482"
SQ   SEQUENCE   155 AA;  16611 MW;  A1B0CDF5F66F3B93 CRC64;
     MASATTSDHA KQAGGAHSRQ RDSGLLDQLG KLFGQEGSRK VPEKGKEPAT RSVLMAPTTH
     KAHQGARRQT DDSPVVHFFK NMMSPKKAPV QQKAKSGASR AITKFIWGTD GQRAHYGAAG
     SSKSKDGFRG RRDGSGTLSS FFKMGKKGEG SPARR