Ataxia-telangiectasia: structural diversity of untranslated sequences suggests complex post-transcriptional regulation of ATM gene expression

• Published in: Nucleic acids research 1997-05, Vol.25 (9), p.1678-1684
• Main Authors: Savitsky, Kinneret, Uziel, Tamar, Gilad, Shlomit, Sartiel, Adam, Shiloh, Yosef, Rotman, Galit, Platzer, Matthias, Rosenthal, Andre, Elroy-Stein, Orna
• Format: Article
• Language: English
• Subjects: Ataxia Telangiectasia - genetics; Ataxia Telangiectasia Mutated Proteins; Base Sequence; Cell Cycle Proteins; Cell Line; DNA; DNA-Binding Proteins; Humans; Jurkat Cells; Male; Molecular Sequence Data; Protein Biosynthesis; Protein-Serine-Threonine Kinases; Proteins - genetics; Proteins - metabolism; RNA Processing, Post-Transcriptional; RNA, Messenger - genetics; Tumor Suppressor Proteins
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/25.9.1678

Mutations in the ATM gene are responsible for the multisystem disorder ataxia-telangiectasia, characterized by neurodegeneration, immune deficiency and cancer predisposition. While no alternative splicing was identified within the coding region, the first four exons of the ATM gene, which fall within the 5′ untranslated region (UTR), undergo extensive alternative splicing. We identified 12 different 5′ UTRs that show considerable diversity in length and sequence contents. These mRNA leaders, which range from 150 to 884 nucleotides (nt), are expected to form variable secondary structures and contain different numbers of AUG codons. The longest 5′ UTR contains a total of 18 AUGs upstream of the translation start site. The 3′ UTR of 3590 nt is contained within a single 3′ exon. Alternative polyadenylation results in 3′ UTRs of varying lengths. These structural features suggest that ATM expression might be subject to complex posttranscriptional regulation, enabling rapid modulation of ATM protein level in response to environmental stimuli or alterations in cellular physiological states.