Molecular analysis of mutations affecting hprt mRNA splicing in human T-lymphocytes in vivo

✍ Scribed by Anna M. Rossi; Ad D. Tates; Albert A. Van Zeeland; Harry Vrieling

• Publisher: John Wiley and Sons
• Year: 1992
• Tongue: English
• Weight: 570 KB
• Volume: 19
• Category: Article
• ISSN: 0893-6692
• DOI: 10.1002/em.2850190103

✦ Synopsis

Molecular analysis of hypoxanthine-guanine

analyzed in more detail by sequencing the gephosphoribosyltransferase (hprt) cDNA from nomic regions flanking the mis-spliced exon.

6-thioguanine-resistant T-lymphocytes cloned

Base pair substitutions or small deletions causfrom smoking and non-smoking adult donors ing defective splicing were either detected in showed that 35% of these mutants were defec-exon sequences or in splice site consensus setive in splicing of hprt mRNA. Among a set of 42 quences of introns. Furthermore, genomic delehprt splice mutants, we observed i) complete tions encompassing entire exons were found. In loss of one or more exons, ii) partial loss of one some mutants, the alteration responsible for exon, or iii) inclusion of part of an intron se-incorrect splicing could not be identified, sugquence between adjocent exons. Loss of exon 4 gesting that the target sequence for splice muwas significantly more frequent than of the other totions is larger than merely the splice junctions. exons, suggesting that the sequences that regu-Molecular characterization of hprt splice mutalate splicing of this exon are either larger than tions will lead to the identification of specific those of the other exons or especially prone to sequences regulating splicing of hprt mRNA and mutation. In order to identify the molecular will reveal whether the mutational spectrum in nature of DNA alterations causing aberrant splice mutants is similar to that found in the hprt splicing of hprt mRNA, 17 splice mutants were coding region.