title: Genomic organization and mapping of the gene encoding the PP2A B56gamma regulatory subunit.
abstract: Protein phosphatase 2A (PP2A) is a major serine/threonine phosphatase that regulates a wide variety of cellular processes. The enzymatic activity and intracellular localization of PP2A are determined by three distinct families of cellular regulatory subunits (B, B'', and B''). The B' subunit, also known as B56, is the most diverse, consisting of five isoforms (alpha, beta, gamma, delta, and epsilon). The gene encoding B56gamma has been designated as PPP2R5C and encodes three differentially spliced variants: B56gamma1, -gamma2, and -gamma3. However, conflicting chromosomal loci have been reported in human genomic databases. The original cytogenetic mapping placed the gene on chromosome 3p21.3, whereas subsequent studies using radiation hybrid analysis localized PPP2R5C to chromosome 14q. In this study, by radiation hybrid mapping, FISH analysis, BAC clone sequencing, and RT-PCR analysis, we show that the functional gene PPP2R5C exists at 14q32.2 and gives rise to three splicing variants, B56gamma1, -gamma2, and -gamma3, whereas a nonfunctional B56gamma1 pseudogene, PPP2R5CP, is present at 3p21.3. We also report the genomic organization of both the functional gene and the pseudogene.
authors.affiliation: Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, 6000 Harry Hines Blvd., Dallas, Texas 75390, USA.
authors.forename: Sabeeha
authors.initials: S
authors.lastname: Muneer
authors.forename: Vivek
authors.initials: V
authors.lastname: Ramalingam
authors.forename: Robert
authors.initials: R
authors.lastname: Wyatt
authors.forename: Roger A
authors.initials: RA
authors.lastname: Schultz
authors.forename: John D
authors.initials: JD
authors.lastname: Minna
authors.forename: Craig
authors.initials: C
authors.lastname: Kamibayashi
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D015894:Genome, Human; D006801:Humans; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000235:genetics*; D054648:Protein Phosphatase 2
chemical_list: D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2