ID LALBA_RABIT Reviewed; 141 AA.
AC P00716; Q9TQT7;
DT 21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT 01-DEC-2000, sequence version 2.
DT 24-JAN-2024, entry version 130.
DE RecName: Full=Alpha-lactalbumin;
DE AltName: Full=Lactose synthase B protein;
DE Flags: Precursor;
GN Name=LALBA;
OS Oryctolagus cuniculus (Rabbit).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC Eutheria; Euarchontoglires; Glires; Lagomorpha; Leporidae; Oryctolagus.
OX NCBI_TaxID=9986;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA].
RC STRAIN=New Zealand white; TISSUE=Mammary gland;
RA Pak K.-W., Kim S.J., Min W.-K., Park I.-Y., Huang H., Kim S.-W., Lee K.-K.;
RT "Cloning of the rabbit alpha-lactalbumin gene and characterization of its
RT promoter in cultured mammary-cells.";
RL Submitted (JAN-1999) to the EMBL/GenBank/DDBJ databases.
RN [2]
RP PROTEIN SEQUENCE OF 20-141.
RX PubMed=497176; DOI=10.1021/bi00590a024;
RA Hopp T.P., Woods K.R.;
RT "Primary structure of rabbit alpha-lactalbumin.";
RL Biochemistry 18:5182-5191(1979).
CC -!- FUNCTION: Regulatory subunit of lactose synthase, changes the substrate
CC specificity of galactosyltransferase in the mammary gland making
CC glucose a good acceptor substrate for this enzyme. This enables LS to
CC synthesize lactose, the major carbohydrate component of milk. In other
CC tissues, galactosyltransferase transfers galactose onto the N-
CC acetylglucosamine of the oligosaccharide chains in glycoproteins.
CC -!- SUBUNIT: Lactose synthase (LS) is a heterodimer of a catalytic
CC component, beta1,4-galactosyltransferase (beta4Gal-T1) and a regulatory
CC component, alpha-lactalbumin (LA).
CC -!- SUBCELLULAR LOCATION: Secreted.
CC -!- TISSUE SPECIFICITY: Mammary gland specific. Secreted in milk.
CC -!- SIMILARITY: Belongs to the glycosyl hydrolase 22 family.
CC {ECO:0000255|PROSITE-ProRule:PRU00680}.
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DR EMBL; AF124257; AAD56599.1; -; mRNA.
DR EMBL; AF123893; AAD56598.1; -; Genomic_DNA.
DR RefSeq; NP_001075521.1; NM_001082052.1.
DR RefSeq; XP_008254616.1; XM_008256394.2.
DR RefSeq; XP_017197107.1; XM_017341618.1.
DR AlphaFoldDB; P00716; -.
DR SMR; P00716; -.
DR STRING; 9986.ENSOCUP00000024236; -.
DR GlyCosmos; P00716; 1 site, No reported glycans.
DR PaxDb; 9986-ENSOCUP00000013596; -.
DR Ensembl; ENSOCUT00000023351.1; ENSOCUP00000024236.1; ENSOCUG00000015834.3.
DR GeneID; 100008717; -.
DR KEGG; ocu:100008717; -.
DR CTD; 3906; -.
DR eggNOG; ENOG502T8BJ; Eukaryota.
DR GeneTree; ENSGT00940000161726; -.
DR HOGENOM; CLU_111620_0_1_1; -.
DR InParanoid; P00716; -.
DR OMA; KCELSQV; -.
DR OrthoDB; 5344399at2759; -.
DR Proteomes; UP000001811; Chromosome 4.
DR Bgee; ENSOCUG00000015834; Expressed in testis and 3 other cell types or tissues.
DR ExpressionAtlas; P00716; baseline.
DR GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR GO; GO:0005509; F:calcium ion binding; IEA:InterPro.
DR GO; GO:0004461; F:lactose synthase activity; IEA:InterPro.
DR GO; GO:0005989; P:lactose biosynthetic process; IEA:UniProtKB-KW.
DR Gene3D; 1.10.530.10; -; 1.
DR InterPro; IPR001916; Glyco_hydro_22.
DR InterPro; IPR019799; Glyco_hydro_22_CS.
DR InterPro; IPR000545; Lactalbumin.
DR InterPro; IPR023346; Lysozyme-like_dom_sf.
DR PANTHER; PTHR11407:SF32; ALPHA-LACTALBUMIN; 1.
DR PANTHER; PTHR11407; LYSOZYME C; 1.
DR Pfam; PF00062; Lys; 1.
DR PRINTS; PR00136; LACTALBUMIN.
DR PRINTS; PR00135; LYZLACT.
DR SMART; SM00263; LYZ1; 1.
DR SUPFAM; SSF53955; Lysozyme-like; 1.
DR PROSITE; PS00128; GLYCOSYL_HYDROL_F22_1; 1.
DR PROSITE; PS51348; GLYCOSYL_HYDROL_F22_2; 1.
PE 1: Evidence at protein level;
KW Calcium; Direct protein sequencing; Disulfide bond; Glycoprotein;
KW Lactose biosynthesis; Metal-binding; Milk protein; Reference proteome;
KW Secreted; Signal.
FT SIGNAL 1..19
FT /evidence="ECO:0000269|PubMed:497176"
FT CHAIN 20..141
FT /note="Alpha-lactalbumin"
FT /id="PRO_0000018448"
FT DOMAIN 20..141
FT /note="C-type lysozyme"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00680"
FT BINDING 101
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250|UniProtKB:P00711"
FT BINDING 106
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250|UniProtKB:P00711"
FT BINDING 107
FT /ligand="Ca(2+)"
FT /ligand_id="ChEBI:CHEBI:29108"
FT /evidence="ECO:0000250|UniProtKB:P00711"
FT CARBOHYD 64
FT /note="N-linked (GlcNAc...) asparagine"
FT DISULFID 25..139
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00680"
FT DISULFID 47..130
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00680"
FT DISULFID 80..96
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00680"
FT DISULFID 92..110
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00680"
FT CONFLICT 75..76
FT /note="SD -> NS (in Ref. 2; AA sequence)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 141 AA; 16082 MW; A41C125B3E774544 CRC64;
MMPLVPLLLV SIVFPGIQAT QLTRCELTEK LKELDGYRDI SMSEWICTLF HTSGLDTKIT
VNNNGSTEYG IFQISDKLWC VSKQNPQSKN ICDTPCENFL DDNLTDDVKC AMKILDKEGI
DHWLAHKPLC SENLEQWVCK K
//
