Syntaxin 1A and 1B display distinct distribution patterns in the rat peripheral nervous system
Section snippets
Antibodies
Anti-syntaxin 1 antibodies were raised in rabbits against (His)6-fusion proteins that contained the cytosolic domain of either syntaxin 1A and 1B. These antisera were further purified to obtain two antibody preparations that recognized syntaxin 1A and syntaxin 1B in a separate manner (named BR1A and BR1B, respectively). Purification procedures and characteristics of these antibodies have been previously described.[42]Monoclonal antobodies against HPC1/syntaxin[5]and SV2[12]were kindly given by
Antibody specificity against syntaxin 1A and 1B
Equivalent amounts of both recombinant (His)6-syntaxin proteins were resolved by electrophoresis and proteins were stained with Coomassie Blue. (His)6-syntaxin 1A migrated faster than (His)6-syntaxin 1B, 35 and 42 being their apparent mol. wt, respectively (Fig. 1A). Western blots using HPC1/syntaxin, BR1A and BR1B antibodies are shown in Fig. 1B. HPC1/syntaxin monoclonal antibodies recognized both syntaxin 1 isoforms. BR1A and BR1B antibodies recognized the appropiate isoform against which
Discussion
Since their original description, different members of the syntaxin family (syntaxin 1–6) have been described in various rat tissues.7, 8In particular, the syntaxin 1A and 1B isoforms have been identified in neural and neuroendocrine tissues.1, 6, 25, 26A recent immunocytochemical study revealed striking differences between the distribution of the syntaxin 1 isoforms in the rat CNS.[42]Interestingly, CNS areas that are known to be involved in sensory functions contained intense labelling for
Conclusions
The distinct expression pattern of syntaxin 1A and 1B in the rat peripheral nervous system is shown by the use of specific syntaxin 1 isoform antibodies. The different distribution of the two neuronal syntaxin isoforms could be related to isoform-specific biochemical properties involved in the exocytotic process.
Acknowledgements
The authors wish to thank Drs C. J. Barnstable, K. Buckley and R. Jahn for their generous gift of antibodies and J. Ballabriga for his expert advice. We are grateful to I. Gómez de Aranda for excellent technical assistance. G.M. is in receipt of a fellowship from the Generalitat de Catalunya. This study was supported by a grant from DGICYT and from E.U. project BMH4-CT96-15864.
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