IDENTIFICATION AND DEVELOPMENTAL EXPRESSION OF A BOMBYX-MORI ALPHA-TUBULIN GENE

A cDNA clone isolated from the wing discs at the metamorphosis of Bomb yx mori during the period of morphogenesis has been characterized. The amino acid sequence predicted for the putative protein is highly homo logous to the Drosophila alpha 1-tubulin. This is the first alpha-tubu lin gene isolated in Bombyx mori and other isotype sequences are prese nt in the Bombyx genome. The transcript is detected in the wing discs at every postembryonic stage examined, and is also expressed in other tissues, but at different levels. Although the mRNA level is maximum w hen the 20-hydroxyecdysone titre is high, its accumulation is independ ent of the hormone level both in vivo and in vitro. Significance of th e accumulation of the mRNA of an ubiquitous alpha-tubulin in developin g wing discs is discussed by comparison with our knowledge of the alph a-tubulin family in Drosophila and in other organisms. (C) 1998 Elsevi er Science B.V.