Acetylcholinesterase (AChE) is found in a variety of structural Forms in mammalian nerve and muscle tissues. These forms are different multimers of catalytic subunits, which appear highly related by enzymological and immunological critieria. Some heterogeneity among subunits is generated by post.translational modifications of the catalytic subunit. Dr. Rosenberry will determine the extent to which multiple AChE genes, distinct messenger RNAs (mRNA), and post.transcriptional processing contribute to the diversity of AChE forms. He has isolated a cDNA clone from a human brain cDNA library which encodes protein sequences highly related to those found in Torpedo AChE, BuChE, and Torpedo AChE protein sequences will allow the confirmation of a clone as one encoding AChE or BuChE. Molecular techniques (nucleic acid sequencing and restriction enzyme mapping) will reveal whether multiple AChE cDNAs exist, the primary amino acid sequence of AChE catalytic subunits, whether multiple catalytic subunits exists, and by inference, the diversity of AChE mRNAs. The latter point will be confirmed by hybridization of AChE clones to Northern blot transfers of mRNA from tissues expressing different AChE forms. These cDNA clones will ultimately allow him to isolate genomic AChE DNA clones. The diversity or singularity of AChE gene sequences can then be determined and the relation to AChE mRNA forms examined. Once AChE cloned sequences are obtained, and the nature of AChE gene and mRNA heterogeneity examined, the materials and information will be available to undertaker examination of the physiological factors regulating the expression of diverse AChE forms.
