Drosophila regulatory factor X is necessary for ciliated sensory neuron differentiation.

Ciliated neurons play an important role in sensory perception in many animals. Modified cilia at dendrite endings serve as sites of sensory signal capture and transduction. We describe Drosophila mutations that affect the transcription factor RFX and genetic rescue experiments that demonstrate its central role in sensory cilium differentiation.

Drosophila regulatory factor X is an embryonic type I sensory neuron marker also expressed in spermatids and in the brain of Drosophila.

We report the expression pattern of a Drosophila transcription factor, Drosophila regulatory factor X (dRFX), which belongs to the RFX winged-helix transcription factor family. dRFX is distributed in type I sensory neuron lineage of the peripheral nervous system throughout Drosophila development and thus represents the first described type I lineage characteristic marker in Drosophila. In addition, dRFX is also detected in the brain throughout development and in spermatids in adult flies.

Cytoplasmic actin A3 gene promoter injected as supercoiled plasmid is transiently active inBombyx mori embryonic vitellophages.

Freshly deposited eggs ofBombyx mori were microinjected with supercoiled plasmid DNA which carried the β-galactosidase coding sequence ofEscherichia coli inserted in place of the coding sequence of theB. mori cytoplasmic actin A3 gene. Transient expression of this fusion gene in the embryo was determined by in situ histochemical detection of enzyme activity.

A cytoplasmic actin gene from the silkworm Bombyx mori is expressed in tissues of endodermal origin and previtellogenic germ cells of transgenic Drosophila.

A cytoplasmic actin gene from Bombyx mori introduced into Drosophila melanogaster by P-element mediated transformation, is efficiently transcribed in larvae, pupae and adults of the host. The exogenous mRNA has the same size as the one observed in the Bombyx cells and the intron located within the coding region is properly excised, indicating a correct recognition of the exogenous sequences by the Drosophila transcriptional and splicing machineries. The expression of the Bombyx gene in Drosophila tissues was determined by transforming flies with a hybrid gene in which a large part of the Bombyx actin coding sequences was replaced by those of the bacterial lac Z gene.

The arrest of embryogenesis at gastrula stage in the diapausing silkwormBombyx mori is related to the synthesis of protein P61.

Two-dimensional protein gels are used to assess systematically changes in protein synthesis in diapausing and non-diapausing early embryos ofBombyx mori throughout natural breakage of diapause by chilling and after artificial prevention of diapause by HCl+ heat-shock treatment. A set of proteins, the heat-shock protein (hsp) 70 family previously described, was synthesized in diapausing and non-diapausing development at the early germ-anlage stage; by contrast, protein 61 (P61; 61 kDa) was synthesized only in the diapausing gastrula stage. The synthesis of P61 decreased during days at 5°C.