TRANSFECTION OF REAGGREGATING EMBRYONIC CHICKEN RETINAL CELLS WITH ANANTISENSE 5'-DNA BUTYRYLCHOLINESTERASE EXPRESSION VECTOR INHIBITS PROLIFERATION AND ALTERS MORPHOGENESIS

The function of the enzyme butyrylcholinesterase (BChE) in the develop ing and mature brain is still unclear. We have inserted 577 bp of the 5' upstream region plus 106 bp of the exon 1 of the rabbit BChE gene i n reverse orientation under control of an SV40 early promoter derivati ve in an expression vector. This vector was introduced by calcium phos phate-mediated transfection into embryonic chicken retina cells during the first days of reaggregation culture. Depending on the retinal ori gin, the transfected cell population forms histotypic retina-like sphe res, so-called rosetted or stratified retinospheroids. We show that an tisense 5'-BChE gene expression decreased the steady-state mRNA level of BChE and the translation of the BChE protein, inhibited proliferati on, and accelerated histogenesis in both cellular systems. The pronoun ced effects of antisense 5'-BChE transfection of spheroids document a key role of BChE during the early reaggregation process of retinal cel ls, most likely by regulating their growth and differentiation.