Gordesky-Gold B, Warrick J M, Bixler A, Beasley J E, Tompkins L
Department of Biology, Temple University, Philadelphia, Pennsylvania 19122, USA.
Genetics. 1995 Apr;139(4):1623-9. doi: 10.1093/genetics/139.4.1623.
Of the many genes that are expressed in the visual system of Drosophila melanogaster adults, some affect larval vision. However, with the exception of one X-linked mutation, no genes that have larval-specific effects on visual system structure or function have previously been reported. We describe the isolation and characterization of two mutant alleles that define the larval photokinesis A (lphA) gene, one allele of which is associated with a P-element insertion at cytogenetic locus 8E1-10. Larvae that express lphA mutations are, like normal animals, negatively photokinetic, but they are less responsive to white light than lphA + controls. Larvae that are heterozygous in trans for a mutant lphA allele and a deficiency that uncovers the lphA locus are blind, which indicates that the mutant allele is hypomorphic. lphA larvae respond normally to odorants and taste stimuli. Moreover, the lphA mutations do not affect adult flies' fast phototaxis or visually driven aspects of male sexual behavior, and electroretinograms recorded from the compound eyes of lphA/deficiency heterozygotes and lphA1/lphA2 females are normal. These observations suggest that the lphA gene affects a larval-specific aspect of visual system function.
在成年黑腹果蝇视觉系统中表达的众多基因里，有些会影响幼虫的视觉。然而，除了一个X连锁突变外，之前尚未报道过对视觉系统结构或功能有幼虫特异性影响的基因。我们描述了定义幼虫光趋动A（lphA）基因的两个突变等位基因的分离和特征，其中一个等位基因与细胞遗传学位点8E1 - 10处的P元素插入有关。表达lphA突变的幼虫与正常动物一样具有负向光趋动性，但它们对白光的反应比lphA +对照更弱。对于突变的lphA等位基因和缺失lphA位点的缺失突变体呈反式杂合的幼虫是失明的，这表明该突变等位基因是亚效等位基因。lphA幼虫对气味剂和味觉刺激反应正常。此外，lphA突变不影响成年果蝇的快速光趋性或雄性性行为中视觉驱动的方面，并且从lphA /缺失杂合子和lphA1 / lphA2雌性的复眼中记录的视网膜电图是正常的。这些观察结果表明，lphA基因影响视觉系统功能中幼虫特异性的方面。
