The human HIP gene, overexpressed in primary liver cancer encodes for a C-type carbohydrate binding protein with lactose binding activity.
HIP was originally identified as a gene expression in primary liver cancers, and in normal tissues such as pancreas and small intestine. Based on gene data base homologies, the HIP protein should consist of a signal peptide linked to a single carbohydrate recognition domain. To test this hypothesis HIP and the putative carbohydrate recognition domain encoded by the last 138 C-terminal amino acids, were expressed as glutathione-S-transferase proteins (GST-HIP and GST-HIP-142, respectively). Both recombinant proteins were purified by a single affinity purification step from bacterial lysates and their ability to bind saccharides coupled to trisacryl GF 2000M were tested. Our results show that HIP and HIP-142 proteins bind to lactose, moreover the binding requires divalent cations. Thus the HIP protein is a lactose-binding lectin with the characteristics of a C-type carbohydrate recognition domain of 138 amino acids in the C-terminal region.
Christa
L
L
INSERM U370, CHU Necker, Paris, France.
Felin
M
M
Morali
O
O
Simon
M T
MT
Lasserre
C
C
Brechot
C
C
Sève
A P
AP
D000951:Antigens, Neoplasm; D001483:Base Sequence; D014408:Biomarkers, Tumor; D050260:Carbohydrate Metabolism; D002413:Cations, Divalent; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D018014:Gene Transfer Techniques; D005982:Glutathione Transferase / Q000235:genetics; D006801:Humans; D007785:Lactose / Q000378:metabolism*; D037181:Lectins, C-Type; D008113:Liver Neoplasms / Q000378:metabolism*; D008969:Molecular Sequence Data; D000073718:Pancreatitis-Associated Proteins; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D002413:Cations, Divalent; D037181:Lectins, C-Type; D000073718:Pancreatitis-Associated Proteins; D011506:Proteins; C000612141:REG3A protein, human; D011993:Recombinant Fusion Proteins; D005982:Glutathione Transferase; D007785:Lactose