Disease relevance of B3GALT5

• In gastrointestinal and pancreatic cancer cell lines, the amounts of beta3Gal-T5 transcripts were quite well correlated with the amounts of the sialyl Lewis a antigens [1].
• Endogenous retrovirus long terminal repeats as ready-to-use mobile promoters: the case of primate beta3GAL-T5 [2].
• Competitive reverse transcriptase mediated-polymerase chain reaction shows that the beta3Gal-T5 transcript is expressed in normal colon mucosa but not or poorly in adenocarcinomas [3].
• 2) Both transcript and protein levels of beta3Gal-T5 were determined to be significantly reduced in colon cancer [4].

High impact information on B3GALT5

• We conclude that HNF-1 is at least partially responsible for the tissue-specific activation of the LTR promoter of human beta 1,3-galactosyltransferase 5 [5].
• Treatment with a COX-2 inhibitor, celecoxib, decreased SPan-1 and sialyl Lewis a expression and adherence to endothelial cells. beta 3Gal-T5 and ST3Gal III and IV expression was inhibited by celecoxib and was enhanced by prostaglandin E(2) treatment [6].
• beta1,3-Galactosyltransferase beta3Gal-T5 is highly expressed in the colons of humans and certain primates due to a retroviral long terminal repeat (LTR) acting as a strong promoter [7].
• We identified three novel 5'-UTRs of beta3Gal-T5 mRNA, types A, B, and C, and found widespread expression of the type A transcript at much lower levels than the LTR transcript, the expression of which is restricted to organs of the gastrointestinal tract [7].
• 1) During in vitro differentiation of Caco-2 cells, transcriptional up-regulation of beta3Gal-T5 was observed in correlation with the increase in transcripts for Cdx2 and HNF1alpha [4].

Biological context of B3GALT5

• Transfection experiments demonstrated that HCT-15 cells transfected with the beta3Gal-T5 gene expressed all the type 1 Lewis antigens [1].
• In the present study, a novel beta3Gal-T, named beta3Gal-T5, was isolated from a Colo205 cDNA library using a degenerate primer strategy based on the amino acid sequences of the four human beta3Gal-T genes cloned to date [1].
• The murine beta3gal-t5 gene is also expressed primarily in the colon, despite the absence of an orthologous ERV-L LTR in the mouse genome [2].
• We also present evidence that the functional TF binding sites of the human beta3GAL-T5 LTR promoter were present in the original consensus sequence for this class of LTRs [2].
• We conclude that beta3Gal-T5 down-regulation plays a relevant role in determining the cancer-associated glycosylation pattern of N-glycans [3].

Anatomical context of B3GALT5

• Among six beta3Gal-Ts cloned to date, beta3Gal-T5 is an essential enzyme for the synthesis of type 1 chain in epithelium of digestive tracts or pancreatic tissue [4].
• In the present study, we found that the transcriptional regulation of the beta3Gal-T5 gene is controlled by homeoproteins, i.e. members of caudal-related homeobox protein (Cdx) and hepatocyte nuclear factor (HNF) families [4].
• A clone permanently expressing an antisense fragment of beta 3Gal-T5 was obtained from the human pancreas adenocarcinoma cell line BxPC3 and characterized [8].

Associations of B3GALT5 with chemical compounds

• In addition, beta3Gal-T5 is a key enzyme that determines the amounts of the type 1 Lewis antigens including the sialyl Lewis a antigen [1].
• This result indicates that beta3Gal-T5 expression prevents poly-N-acetyllactosamine and sialyl-Lewis x synthesis on N-glycans [3].
• These data indicate that beta 3Gal-T5 suppression turns synthesis of type 1 chain O-glycans to poly N-acetyllactosamine elongation and termination by sLex [8].
• The detection of the biotin tag transferred by beta3Gal-T5 onto BSA-(GlcNAc)17 with streptavidin-enzyme conjugates gave detection limits of 150 pmol of tagged GlcNAc in a Western blot analysis and 1 pmol of tagged GlcNAc in a microtiter plate assay [9].

Regulatory relationships of B3GALT5

• Moreover, recombinant carcinoembryonic antigen purified from a CHO clone expressing Fuc-TIII and beta3Gal-T5 reacts with anti-sialyl-Lewis a and carries type 1 chains on oligosaccharides released by endo-beta-galactosidase [3].

Other interactions of B3GALT5

• It could be demonstrated for the first time, by use of UDP-6-biotinyl-Gal as a donor substrate, that the human recombinant galactosyltransferases beta3Gal-T5, beta4Gal-T1, and beta4Gal-T4 mediate biotinylation of the neoglycoconjugate bovine serum albumin-p-aminophenyl N-acetyl-beta-D-glucosaminide (BSA-(GlcNAc)17) and ovalbumin [9].

References