title: Vesicular monoamine transporter-1 (VMAT-1) mRNA and immunoreactive proteins in mouse brain.
abstract: OBJECTIVE
  Vesicular monoamine transporter 1 (VMAT-1) mRNA and protein were examined (1) to determine whether adult mouse brain expresses full-length VMAT-1 mRNA that can be translated to functional transporter protein and (2) to compare immunoreactive VMAT-1 proteins in brain and adrenal.
  
  
  METHODS
  VMAT-1 mRNA was detected in mouse brain with RT-PCR. The cDNA was sequenced, cloned into an expression vector, transfected into COS-1 cells, and cell protein was assayed for VMAT-1 activity. Immunoreactive proteins were examined on western blots probed with four different antibodies to VMAT-1.
  
  
  RESULTS
  Sequencing confirmed identity of the entire coding sequences of VMAT-1 cDNA from mouse medulla oblongata/pons and adrenal to a Gen-Bank reference sequence. Transfection of the brain cDNA into COS-1 cells resulted in transporter activity that was blocked by the VMAT inhibitor reserpine and a proton ionophore, but not by tetrabenazine, which has a high affinity for VMAT-2. Antibodies to either the C- or N- terminus of VMAT-1 detected two proteins (73 and 55 kD) in transfected COS-1 cells. The C-terminal antibodies detected both proteins in extracts of mouse medulla/pons, cortex, hypothalamus, and cerebellum but only the 73 kD protein and higher molecular weight immunoreactive proteins in mouse adrenal and rat PC12 cells, which are positive controls for rodent VMAT-1.
  
  
  CONCLUSIONS
  These findings demonstrate that a functional VMAT-1 mRNA coding sequence is expressed in mouse brain and suggest processing of VMAT-1 protein differs in mouse adrenal and brain.
authors.affiliation: Department of Biology, Virginia Commonwealth University, Richmond, VA 23284, USA.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Ashe
authors.forename: Wan-Ling
authors.initials: WL
authors.lastname: Chiu
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Khalifa
authors.forename: Antoine N
authors.initials: AN
authors.lastname: Nicolas
authors.forename: Bonnie L
authors.initials: BL
authors.lastname: Brown
authors.forename: Randall R
authors.initials: RR
authors.lastname: De Martino
authors.forename: Clayton P
authors.initials: CP
authors.lastname: Alexander
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Waggener
authors.forename: Krista
authors.initials: K
authors.lastname: Fischer-Stenger
authors.forename: Jennifer K
authors.initials: JK
authors.lastname: Stewart
mesh_terms: D000311:Adrenal Glands / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D001923:Brain Chemistry / Q000235:genetics* / Q000276:immunology; D019556:COS Cells; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002522:Chlorocebus aethiops; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D007150:Immunohistochemistry; D051379:Mice; D008808:Mice, Inbred CBA; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D016716:PC12 Cells; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050493:Vesicular Monoamine Transport Proteins / Q000096:biosynthesis* / Q000235:genetics*
chemical_list: D018076:DNA, Complementary; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; C493450:Slc18a1 protein, mouse; D050493:Vesicular Monoamine Transport Proteins