Isolation and characterization of GT335, a novel human gene conserved in Escherichia coli and mapping to 21q22.3.
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.
Lafrenière
R G
RG
Centre for Research in Neuroscience, McGill University, Montreal, Quebec, H3G 1A4, Canada. bhgr@musicb.mcgill.ca
Rochefort
D L
DL
Kibar
Z
Z
Fon
E A
EA
Han
F
F
Cochius
J
J
Kang
X
X
Baird
S
S
Korneluk
R G
RG
Andermann
E
E
Rommens
J M
JM
Rouleau
G A
GA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins; D015139:Blotting, Southern; D002874:Chromosome Mapping; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics*; D016384:Consensus Sequence; D003360:Cosmids / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics*; D015870:Gene Expression; D005796:Genes; D018398:Homeodomain Proteins; D006801:Humans; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D009124:Muscle Proteins / Q000235:genetics*; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational; D011506:Proteins; D012326:RNA Splicing; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D000072056:Transcription Factor HES-1; D015027:Zebrafish / Q000235:genetics
D051792:Basic Helix-Loop-Helix Proteins; D018076:DNA, Complementary; D018398:Homeodomain Proteins; D024101:Mitochondrial Proteins; D009124:Muscle Proteins; D011506:Proteins; D000072056:Transcription Factor HES-1; C489737:GAD3 protein, human; C078493:HES1 protein, human