ESSENTIAL GENES AND DEFICIENCIES IN THE UNC-22 IV REGION OF CAENORHABDITIS ELEGANS

[摘要] Five formaldehyde-induced deficiencies that uncover unc-22 IV , a gene affecting muscle structure in the nematode Caenorhabditis elegans were isolated and positioned. The largest deficiency, sDf2 , extends in both directions from unc-22 and is approximately 1.0-2.0 map units in length. The other four deficiencies, sDf7, sDf8, sDf9 and sDf10 , are all smaller than sDf2 and are located within the region uncovered by this deficiency. Thirty-seven ethyl methanesulfonate-induced lethal and sterile mutations linked to unc-22 were isolated and tested for complementation with sDf2 . Nineteen lethal mutations failed to complement sDf2 . Sixteen of these were further positioned by recombination mapping and also by deficiency mapping with sDf7, sDf8, sDf9 and sDf10 . These sixteen mutations define 11 new essential genes in this region. Eight of the genes lie in a 0.9-map unit interval to the left of unc-22 , whereas the three remaining genes lie in a region of about 0.2 map units to the right of unc-22 . We believe that two of the essential genes identified in this study, let-56 and let-52 , are the adjacent genes on either side of unc-22 . The lethal mutations exhibit a wide range of terminal phenotypes: from first stage larva to sterile adult.

[学科分类] 医学（综合）