High impact information on AMPD2

• Previous molecular studies have reported two genes, AMPD1 and AMPD2, that produce isoform M and L transcripts, respectively [1].
• Nucleotide and predicted amino acid comparisons with the 264 base pairs of proposed coding sequences in the rat AMPD2 cDNA demonstrate 91% similarity and identity, respectively [2].
• This results in a 3292-base pair cDNA proposed to contain the entire AMPD2 open reading frame, which would encode a 760-amino acid polypeptide with a predicted subunit molecular mass of 88.1 kDa [2].
• Characterization of human AMP deaminase 2 (AMPD2) gene expression reveals alternative transcripts encoding variable N-terminal extensions of isoform L [3].
• The Chinese hamster GNAI3 gene maps to chromosome 1 within a 120-kb fragment that also comprises the AMPD2 and GSTM genes [4].

Biological context of AMPD2

• Conversely, residues 129-183 in the AMPD2 polypeptide reduce actomyosin binding of isoform L. In addition, residues 1-48 in the AMPD3 polypeptide dramatically suppress contractile protein binding of isoform E, thus allowing this enzyme to participate in other intracellular interactions [5].
• Inspection of genomic DNA sequence reveals that AMPD2 promoter regions lack readily identifiable TATA boxes and are G + C-rich, particularly in the region of multiple transcription initiation sites in exon 1A [6].
• Composed of nineteen exons and eighteen intervening sequences spanning nearly 14 kb of genomic DNA, the human AMPD2 gene is positioned on the short arm of chromosome 1 near the p13.3 boundary [6].
• The AMPD2 gene is presently unlocalized in human genome; its proposed position on mouse Chr 3 is at 53.4 cM [7].
• This study describes the recombinant overexpression of three naturally occurring human AMPD2 proteins, 1A/2, 1B/2, and 1B/3, that differ by N-terminal extensions of 47-128 amino acids, resulting from the use of multiple promoters and alternative splicing events [8].

Associations of AMPD2 with chemical compounds

• The identity of a gene coamplified with the adenylate deaminase 2 gene (AMPD2) in coformycin-resistant cells was determined by analysis of its genomic sequence [4].
• Expression of non-muscle isoforms of creatine kinase (CK-B) and AMP deaminase (AMPD2 and AMPD3) was found in contrast to muscle-restricted isoforms [9].
• A survey of protease inhibitors reveals that E-64 and leupeptin are able to maintain the subunit structure of each AMPD2 protein when they are included in extraction and storage buffers [8].

Regulatory relationships of AMPD2

• When placed in a prokaryotic expression vector, the human AMPD2 cDNA expresses AMP deaminase activity which can be precipitated with polyclonal antisera specific for isoform L [2].

Other interactions of AMPD2

• We show here that the GNAT2 gene, which is inactive in the fibroblastic cells, lies within the 20 kb separating the transcriptionally active GNAI3 and AMPD2 genes [7].

Analytical, diagnostic and therapeutic context of AMPD2

• A previous report described almost the full-length cDNA sequence and part of the human AMPD2 gene and also presented Northern blot evidence for multiple transcripts in brain [3].
• Gel filtration chromatography of these three purified AMPD2 enzymes comprised of intact subunits reveals that each migrates faster than expected, resulting in observed molecular masses significantly greater than those predicted for native tetrameric structures [8].
• Molecular cloning of AMP deaminase isoform L. Sequence and bacterial expression of human AMPD2 cDNA [2].

References