A novel member of the glycosyltransferase family, β3Gn-T2, highly downregulated in invasive human bladder transitional cell carcinomas

✍ Scribed by Irina Gromova; Pavel Gromov; Julio E. Celis

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 408 KB
• Volume: 32
• Category: Article
• ISSN: 0899-1987
• DOI: 10.1002/mc.1065

✦ Synopsis

Abstract

Differential display reverse transcription (DDRT)–polymerase chain reaction (PCR) was used to compare the transcriptomes of invasive and noninvasive fresh human bladder transitional cell carcinomas. A differentially expressed novel gene sharing structural similarity with the human β3‐galactosyltransferase family, β‐1,3‐N‐acetylglucosaminyltransferase‐T2 (β3Gn‐T2), was identified. The full‐length β3Gn‐T2 cDNA, containing a complete open reading frame of 1193 bp, was cloned and sequenced. β3Gn‐T2 exhibited 29–41% homology to the multigene β3‐galactosyltransferase family. Expression of the full‐length β3Gn‐T2 cDNA in an in vitro coupled transcription/translation assay yielded a primary translation product with an apparent Mr of 46 kDa, which is in agreement with the predicted 397‐amino‐acid protein encoded by β3Gn‐T2. Multiple peptide alignment showed several sequence motifs corresponding to putative catalytic domains that are conserved throughout all members of the β3‐galactosyltransferase family, namely, a type II transmembrane domain, a conserved DxD motif, an N‐glycosylation site, and five conserved cysteins. By RT‐PCR strong downregulation of β3Gn‐T2 expression was noted in invasive human bladder transitional cell carcinomas (16 fresh biopsy samples: grade III, T2–T4) compared with their noninvasive counterparts (15 fresh biopsies: grade II, Ta), suggesting that β3Gn‐T2 may be involved in cancer progression. © 2001 Wiley‐Liss, Inc.