ID   FIBL_GALME              Reviewed;         267 AA.
AC   Q26427;
DT   01-DEC-2000, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1996, sequence version 1.
DT   25-MAY-2022, entry version 62.
DE   RecName: Full=Fibroin light chain;
DE            Short=Fib-L;
DE   AltName: Full=L-fibroin;
DE   AltName: Full=PG-1;
DE   Contains:
DE     RecName: Full=Fibroin light chain, short form;
DE   Flags: Precursor;
GN   Name=FIBL;
OS   Galleria mellonella (Greater wax moth).
OC   Eukaryota; Metazoa; Ecdysozoa; Arthropoda; Hexapoda; Insecta; Pterygota;
OC   Neoptera; Endopterygota; Lepidoptera; Glossata; Ditrysia; Pyraloidea;
OC   Pyralidae; Galleriinae; Galleria.
OX   NCBI_TaxID=7137;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA], AND PROTEIN SEQUENCE OF 17-27.
RC   TISSUE=Posterior silk gland;
RX   PubMed=7715595; DOI=10.1007/bf00425815;
RA   Zurovec M., Vaskova M., Kodrik D., Sehnal F., Kumaran A.K.;
RT   "Light-chain fibroin of Galleria mellonella L.";
RL   Mol. Gen. Genet. 247:1-6(1995).
CC   -!- FUNCTION: It is likely that the major role of L-chain is to prevent the
CC       retention of H-chain in ER by forming the disulfide linkage.
CC       {ECO:0000250}.
CC   -!- SUBUNIT: Silk fibroin elementary unit consists in a disulfide-linked
CC       heavy and light chain and a p25 glycoprotein in molar ratios of 6:6:1.
CC       This results in a complex of approximately 2.3 MDa.
CC   -!- SUBCELLULAR LOCATION: Secreted.
CC   -!- TISSUE SPECIFICITY: Produced exclusively in the posterior (PSG) section
CC       of silk glands, which are essentially modified salivary glands.
CC   -!- DEVELOPMENTAL STAGE: Expressed in the posterior silk glands throughout
CC       the penultimate and last larval instars. Declines in immobile pupae and
CC       disappears within the next 12 hours when insects pupate.
CC   -!- PTM: Partially N-terminally processed to yield a short form which lacks
CC       the first two residues of the long form. {ECO:0000250}.
CC   -!- PTM: The interchain disulfide bridge is essential for the intracellular
CC       transport and secretion of fibroin. {ECO:0000250}.
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DR   EMBL; S77817; AAB34044.1; -; mRNA.
DR   PIR; S54713; S54713.
DR   AlphaFoldDB; Q26427; -.
DR   Proteomes; UP000504614; Unplaced.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   InterPro; IPR008660; L-fibroin.
DR   Pfam; PF05849; L-fibroin; 1.
DR   PIRSF; PIRSF005765; L-fibroin; 1.
PE   1: Evidence at protein level;
KW   Acetylation; Direct protein sequencing; Disulfide bond; Reference proteome;
KW   Secreted; Signal; Silk protein.
FT   SIGNAL          1..16
FT                   /evidence="ECO:0000269|PubMed:7715595"
FT   CHAIN           17..267
FT                   /note="Fibroin light chain"
FT                   /id="PRO_0000021257"
FT   CHAIN           19..267
FT                   /note="Fibroin light chain, short form"
FT                   /evidence="ECO:0000250"
FT                   /id="PRO_0000389560"
FT   MOD_RES         19
FT                   /note="N-acetylserine; in short form"
FT                   /evidence="ECO:0000250"
FT   DISULFID        103..162
FT                   /evidence="ECO:0000255"
FT   DISULFID        195
FT                   /note="Interchain (with heavy chain)"
FT                   /evidence="ECO:0000250"
FT   CONFLICT        24
FT                   /note="Q -> E (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   267 AA;  27079 MW;  2A01050F9F120F6F CRC64;
     MLPFVLVLLV ATSALAAPSV VISQDNINNI APRVGNGRPI SSALIDRAFE IVDGGDTNIY
     ILTIQQILND LADQPDGLSQ SLAVTQAVAA LGELATGVPG NSCEAAAVID AYANSVRTGD
     NSALSIAVAN YINRLSSNIG LISQLASNPD SLRYSSGPAG NCAGGGRSYQ FEAAWDAVLN
     NANPYQIGLI NEEYCAARRL YNAFNSRSNN VGAAITAGAV VAQTQAAQII LPSLVNVLSA
     VAAGGNVAGA AAQAGQALAN AAANVQL