The glypicans comprise a family of glycosylphosphatidylinositol-anchored heparan sulfate proteoglycans. Mutations in
the gene encoding glypican-3 (GPC3) implicate glypicans in the control of cell growth and division.
NCBI Summary:
The glypicans comprise a family of glycosylphosphatidylinositol-anchored heparan sulfate proteoglycans. The glypicans have been implicated in the control of cell growth and division. Glypican 6 is a putative cell surface coreceptor for growth factors, extracellular matrix proteins, proteases and anti-proteases.
General function
Comment
The glypicans compose a family of glycosylphosphatidylinositol-anchored
heparan sulfate proteoglycans. Mutations in dally, a gene encoding a Drosophila
glypican, and in GPC3, the gene for human glypican-3, implicate glypicans in the
control of cell growth and division.
The glypican-6 mRNA encodes a protein of 555 amino
acids that is most homologous to glypican-4 (identity of 63%). Expression of this
protein in Namalwa cells shows a core protein of approximately 60 kDa that is
substituted with heparan sulfate only. GPC6, the gene encoding human glypican-6,
contains nine exons. Like GPC5, the gene encoding glypican-5, GPC6 maps to
chromosome 13q32. Clustering of the GPC5/GPC6 genes on chromosome 13q32
is strongly reminiscent of the clustering of the GPC3/GPC4 genes on chromosome
Xq26 and suggests GPCs arose from a series of gene and genome duplications.
Based on similarities in sequence and gene organization, glypican-1, glypican-2,
glypican-4, and glypican-6 appear to define a subfamily of glypicans, differing
from the subfamily comprising so far glypican-3 and glypican-5.
Cellular localization
Secreted, Plasma membrane
Comment
Ovarian function
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Expression regulated by
Comment
Ovarian localization
, Follicular Fluid
Comment
By sequencing expressed sequence tag clones
and products of rapid amplifications of cDNA ends, Veugelers M et al 1999 identified a sixth member of the glypican family. Northern
blottings indicate that glypican-6 mRNA is widespread, with prominent
expressions in human fetal kidney and adult ovary.
Growth factor signaling in these tissues might in part be regulated by the presence
of glypican-6 on the cell surface.
Follicle stages
Comment
Paine-Saunders S, et al 1999
reported that a single GPC6 mRNA of 6.2 kb is detected
most abundantly in the ovary, liver, and kidney, with lower levels of mRNA
expression also detected in a wide range of other adult tissues.