Isolation and characterization of GT335, a novel human gene conserved in Escherichia coli and mapping to 21q22.3

• Published in: Genomics (San Diego, Calif.) Vol. 38; no. 3; pp. 264 - 272
• Main Authors: LAFRENIERE, R. G, ROCHEFORT, D. L, ROMMENS, J. M, ROULEAU, G. A, KIBAR, Z, FON, E. A, HAN, F.-Y, COCHIUS, J, KANG, X, BAIRD, S, KORNELUK, R. G, ANDERMANN, E
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier 15.12.1996
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Basic Helix-Loop-Helix Transcription Factors; Biological and medical sciences; Blotting, Southern; Chromosome Mapping; Chromosomes, Human, Pair 21 - genetics; Consensus Sequence; Cosmids - genetics; DNA, Complementary - genetics; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; Gene Expression; Genes; Genes. Genome; Homeodomain Proteins; Humans; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Muscle Proteins - genetics; Polymerase Chain Reaction; Polymorphism, Single-Stranded Conformational; Proteins; RNA Splicing; Sequence Alignment; Sequence Homology, Amino Acid; Transcription Factor HES-1; Zebrafish - genetics; Genetic mapping; Heart; Human; Nucleotide sequence; Escherichia coli; Chromosome G21; Homology; Gene organization; Gene expression; Striated muscle; Conserved sequence; Contig; Complementary DNA; Gene; Bacteria; Enterobacteriaceae
• ISSN: 0888-7543; 1089-8646
• DOI: 10.1006/geno.1996.0627

As part of efforts to identify candidate genes for disorders mapped to 21q22.3, we have constructed a 405-kb cosmid contig encompassing five tightly linked markers mapping to this region. A subset of these cosmids was used to identify cDNA fragments by the method of hybrid selection. We present here the cDNA sequence of one such gene (GT335) mapping to this region. The gene is expressed as a 1.7-kb transcript predominantly in heart and skeletal muscle, potentially displays alternate splicing, and is predicted to encode a protein 268 amino acids in length. GT335 spans an estimated 13 kb of genomic DNA and is split into seven exons. Five of the six introns conform to the GT . . . AG consensus for intronic splice junctions; the sixth contains nonconventional (AT . . . AC) intronic junctions. We screened this gene for single-basepair mutations using single-strand conformation polymorphism and sequence analysis of both cDNA and genomic DNA from a number of unrelated individuals and have identified several sequence variations, two of which cause conservative amino acid substitutions. This gene is well conserved evolutionarily, with homologs identified in zebrafish and Escherichia coli, suggesting that it plays an important role in basic cellular metabolism.