Lg. Wright et al., MOLECULAR CHARACTERIZATION OF THE 71E LATE PUFF IN DROSOPHILA-MELANOGASTER REVEALS A FAMILY OF NOVEL GENES, Journal of Molecular Biology, 255(3), 1996, pp. 387-400
Early metamorphic development in Drosophila melanogaster is initiated
by pulses of the steroid hormone ecdysone, which are transduced into t
issue-specific transcriptional cascades. This process begins with the
hormone-dependent activation of a set of transcription factors (early
genes) that, in turn, activate set of tissue-specific effector genes (
late genes). The 71E cytogenetic region of the salivary gland polytene
genome contains several ecdysone-regulated transcription units. Molec
ular techniques were used to analyze these genes, their transcriptiona
l program and their evolutionary relatedness. We find that this region
contains a cluster of ten coordinately regulated late genes (L71 gene
s) that are organized as five divergently transcribed gene pairs. Maxi
mum parsimony analysis suggests that an ancestral L71 gene duplicated
to form the first gene pair which was, in turn, duplicated to form the
set of gene pairs. The L71 gene products form a family of small, chem
ically basic proteins with a conserved backbone of cysteine residues.
In addition, the 71E region contains another gene (I71-1) with the reg
ulatory and biochemical characteristics of the salivary gland intermol
t glue proteins. (C) 1996 Academic Press Limited