SLC35C1

SLC35C1, or solute carrier family 35 member C1, is a human gene encoding a Golgi membrane transporter that exports GDP-fucose into the Golgi lumen. It is a member of the SLC35 family of nucleotide-sugar transporters, which provide sugar donors to glycosylation enzymes in the secretory pathway.

Biological function

The protein imports GDP-fucose into the Golgi apparatus, supplying fucosyltransferases with substrate needed to generate fucosylated glycoconjugates. This fucosylation is essential for the formation of selectin ligands, such as sialyl-Lewis X, which mediate leukocyte rolling and trafficking during immune responses.

Clinical significance

Mutations in SLC35C1 cause leukocyte adhesion deficiency II (LAD II), also known as congenital disorder of glycosylation IIc. Patients typically present with immunodeficiency, growth retardation, and distinctive features, including defective fucosylation of glycoconjugates and impaired selectin-mediated leukocyte adhesion. The condition follows an autosomal recessive inheritance pattern and can be diagnosed by biochemical evidence of hypofucosylation and confirmed by genetic sequencing.

Structure and localization

The encoded protein is predicted to be a multi-pass Golgi membrane transporter. It is broadly expressed, with notable relevance to hematopoietic tissues given the immunological manifestations of LAD II.

Evolution and related transporters

SLC35C1 is part of the conserved SLC35 family of nucleotide-sugar transporters. It functions alongside other transporters that supply substrates for glycosylation, such as CMP-sialic acid transporters, to support complex glycan synthesis.

See also: SLC35 family, GDP-fucose transport, selectin ligands, leukocyte adhesion deficiency II.