In Drosophila, don juan and don juan like encode proteins of the spermatid nucleus and the flagellum and both are regulated at the transcriptional level by the TAF_II80 cannonball while translational repression is achieved by distinct elements

Abstract

The genes don juan (dj) and don juan like (djl) encode basic proteins expressed in the male germline. Both proteins show a similar expression pattern being localized in the sperm heads during chromatin condensation and along the flagella. Prematurely expressed Don Juan-eGFP and Myc-Don Juan Like localize to the cytoplasm of spermatocytes and in mitochondrial derivatives from the nebenkern stage onward suggesting that both proteins associate with the mitochondria along the flagella in elongated spermatids. Premature expression of Myc-Don Juan Like does not impair spermatogenesis where-as Don Juan-eGFP when prematurely expressed causes male sterility as spermatids fail to individualize. In spite of the sequence identity of 72% on the nucleotide level and 42% on the protein level, the presumptive promoter regions and the untranslated regions of the mRNA are diverged. Our in vivo analysis revealed that don juan and don juan like are transcriptionally and translationally controlled by distinct short cis regulatory regions. Transcription of don juan and don juan like depends on the male germ line specific TAF II 80, Cannonball (Can). Translational repression elements for both mRNAs are localized in the 5 UTR and are capable to form distinct secondary structures in close proximity to the translational initiation codon.

Promoter contribution to the testis-specific expression of Stellate gene family in Drosophila melanogaster

“…Some genes analyzed to date (janus B, gdl, β-tubulin, dhod, sdic, don juan, don juan like, and ocnus), which are expressed only during Drosophila spermatogenesis, also have extremely short promoter regions (Blumer et al, 2002;Hempel et al, 2006;Hense et al, 2007;Michiels et al, 1989;Ranz et al, 2003;Santel et al, 2000;Schulz et al, 1990;Yang et al, 1995;Yanicostas et al, 1989). We found no E-boxes within their promoters, except for a single degenerated E-box upstream TSS in the ocnus promoter (Hense et al, 2007).…”

A novel eIF4G homolog, Off-schedule, couples translational control to meiosis and differentiation inDrosophilaspermatocytes

“…Translational control delays the accumulation of their protein products. This delay is functionally relevant, because precocious don juan accumulation leads to sterility (Hempel et al, 2006). In principle, then, the lack of significant differentiation in eIF4G2 mutants could simply be due to a more pronounced translational delay for key differentiation genes.…”

Three levels of regulation lead to protamine and Mst77F expression in Drosophila

“…Germ cells from male flies mutant for any of these tTAF genes do not enter meiotic division and spermiogenesis. Although the cells mature spermatocytes, they fail to express the high levels of many spermiogenesis-relevant genes of normal spermatocytes (Hempel et al, 2006; Hiller et al, 2004; White-Cooper et al, 1998), which suggests that tTAFs directly and/or indirectly control robust transcription of many genes required for spermatid morphogenesis. Of these spermiogenesis-relevant, tTAF-dependent genes, so far only the promoters of fzo , Mst87F, and dj are known to be bound by tTAFs (Chen et al, 2005, 2011).…”