The cellular and developmental expression of hrs-2 in rat.
The molecular events underlying vesicular trafficking probably involve the formation and dissolution of protein complexes between integral components of the vesicle and its target membrane. SNAP-25 is associated with the plasma membrane and is a component of a core protein complex thought to be essential for neurotransmitter release. We have previously characterized a protein, hrs-2, that interacts with SNAP-25 and inhibits secretion from permeabilized PC12 cells. The cellular localization and developmental expression patterns of a number of proteins involved in the secretion machinery have been documented. To understand more about the possible cellular role of hrs-2, we have examined hrs-2 distribution, developmental expression and subcellular localization in rat tissues and cell lines. We show herein that the distribution of hrs-2 in brain and periphery parallels that of SNAP-23/25, and that recombinant hrs-2 binds to both SNAP-23 and SNAP-25. Hrs-2 mRNA and protein are found almost ubiquitously in neurons in the brain. Hrs-2 mRNA is expressed in the neural tube at E10 and thereafter mRNA and protein levels remain relatively constant in the whole brain through adulthood. In cultured PC12 cells, endogenous hrs-2 is expressed in the cytoplasm and on the limiting membranes of multivesicular bodies. Overexpression of hrs-2 in mammalian cells results in the appearance of large intracellular compartments that are labelled with hrs-2 antibodies. The wide distribution, the interaction with SNAP-23 and the localization on multivesicular body membranes suggest a general role for hrs-2 in cellular machinery.
Tsujimoto
S
S
Department of Neurobiology and Anatomy, The W.M. Keck Center for the Neurobiology of Learning and Memory, University of Texas Medical School, Houston 77030, USA.
Pelto-Huikko
M
M
Aitola
M
M
Meister
B
B
Vik-Mo
E O
EO
Davanger
S
S
Scheller
R H
RH
Bean
A J
AJ
D000251:Adenosine Triphosphatases / Q000096:biosynthesis*; D000818:Animals; D000911:Antibodies, Monoclonal; D001345:Autoradiography; D015152:Blotting, Northern; D015153:Blotting, Western; D001921:Brain / Q000166:cytology / Q000254:growth & development*; D001923:Brain Chemistry; D002352:Carrier Proteins / Q000378:metabolism; D002460:Cell Line; D056827:Endosomal Sorting Complexes Required for Transport; D015151:Immunoblotting; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D017933:Peripheral Nervous System / Q000378:metabolism; D010750:Phosphoproteins; D050766:Qb-SNARE Proteins; D050767:Qc-SNARE Proteins; D012333:RNA, Messenger / Q000096:biosynthesis / Q000302:isolation & purification; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis; D050825:Synaptosomal-Associated Protein 25
D000911:Antibodies, Monoclonal; D002352:Carrier Proteins; D056827:Endosomal Sorting Complexes Required for Transport; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D010750:Phosphoproteins; D050766:Qb-SNARE Proteins; D050767:Qc-SNARE Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; C100493:SNAP23 protein, human; C494210:Snap25 protein, rat; D050825:Synaptosomal-Associated Protein 25; D000251:Adenosine Triphosphatases; C115505:Hgs protein, rat