title: GNAZ in human fetal cochlea: expression, localization, and potential role in inner ear function.
abstract: Dissociation of an activated alpha-subunit from the beta-gamma complex directly regulates secondary messenger proteins. To address the potential role of G proteins expressed in human fetal cochlea, degenerate oligonucleotide primers corresponding to the 3'-end of the conserved region of alpha-subunits were used for polymerase chain reaction amplification of reverse-transcribed total human fetal cochlear mRNAs; GNAZ and GNAQ were isolated. These two G proteins are unique among the G-protein family because they lack a typical pertussis modification site. GNAZ is expressed in high levels in neural tissue while GNAQ is ubiquitously expressed. We characterized GNAZ expression using Northern blots, tissue in-situ hybridization and immunohistochemistry techniques to elucidate the potential role of this protein in inner ear function. Our data suggest that GNAZ may play a role in maintaining the ionic balance of perilymphatic and endolymphatic cochlear fluids.
authors.affiliation: Department of Genetics, Harvard Medical School, Boston, MA, USA.
authors.forename: I
authors.initials: I
authors.lastname: Magovcevic
authors.forename: U
authors.initials: U
authors.lastname: Khetarpal
authors.forename: F R
authors.initials: FR
authors.lastname: Bieber
authors.forename: C C
authors.initials: CC
authors.lastname: Morton
mesh_terms: D001345:Autoradiography; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D003051:Cochlea / Q000196:embryology / Q000378:metabolism*; D004247:DNA / Q000737:chemistry / Q000235:genetics; D007758:Ear, Inner / Q000502:physiology; D005326:Fetal Proteins / Q000096:biosynthesis* / Q000378:metabolism / Q000502:physiology; D019204:GTP-Binding Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010498:Perilymph / Q000378:metabolism / Q000502:physiology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015290:Second Messenger Systems; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D005326:Fetal Proteins; D012333:RNA, Messenger; D004247:DNA; D019204:GTP-Binding Proteins