Sedoheptulokinase (SHPK)

Sedoheptulokinase has weak homology to several carbohydrate kinases, a class of proteins involved in the phosphorylation of sugars as they enter a cell, inhibiting return across the cell membrane. Sequence variation between this novel gene and known carbohydrate kinases suggests the possibility of a different substrate, cofactor or changes in kinetic properties distinguishing it from other carbohydrate kinases. The gene resides in a region commonly deleted in cystinosis patients, suggesting a role as a modifier for the cystinosis phenotype. The genomic region is also rich in Alu repetitive sequences, frequently involved in chromosomal rearrangements. Strongly expressed in liver, kidney and pancreas. Expressed at lower levels in placenta and heart. Very weakly expressed in lung and brain.