LMAN1
LMAN1 is a membrane mannose-specific lectin identified in intracellular compartments. It is a protein marker of the intermediate compartment shuttling between the endoplasmic reticulum (ER) and the cis-Golgi apparatus.
The 510-amino acid LMAN1 protein has a calculated molecular mass of 54 kD and contains a N-terminal signal sequence, a transmembrane segment, and a short cytoplasmic domain with an ER retention motif.
The N-terminal carbohydrate recognition domains of LMAN1, LMAN2L (MIM.609552) and LMAN2 (MIM.609551) are highly conserved, particularly the motifs required for Ca(2+) and mannose binding and the 2 cysteines predicted to be disulfide bonded. The 3 proteins all have C-terminal ER retrieval motifs.
LMAN1 transcripts are detected in all tissues examined, with highest expression in skeletal muscle, kidney, liver, and placenta.
Pathology
genetic diseases of intracellular-membrane transport
- diseases affecting the protein-sorting apparatus
- germline mutations of LMAN1 in combined deficiency of coagulation factors V and VIII
References
Olkkonen VM, Ikonen E. Genetic defects of intracellular-membrane transport. N Engl J Med. 2000 Oct 12;343(15):1095-104. PMID: #11027745#