The lncRNA male-specific abdominal plays a critical role in Drosophila accessory gland development and male fertility

Abstract

Although thousands of long non-coding RNAs (lncRNA) have been identified in the genomes of higher eukaryotes, the precise function of most of them is still unclear. Here, we show that a >65 kb, male-specific, lncRNA, called male-specific abdominal (msa) is required for the development of the secondary cells of the Drosophila male accessory gland (AG). msa is transcribed from within the Drosophila bithorax complex and shares much of its sequence with another lncRNA, the iab-8 lncRNA, which is involved in the development of the central nervous system (CNS). Both lncRNAs perform much of their functions via a shared miRNA embedded within their sequences. Loss of msa, or of the miRNA it contains, causes defects in secondary cell morphology and reduces male fertility. Although both lncRNAs express the same miRNA, the phenotype in the secondary cells and the CNS seem to reflect misregulation of different targets in the two tissues.

Rab‐mediated trafficking in the secondary cells of Drosophila male accessory glands and its role in fecundity

“…Although the PMR starts normally, the mating‐induced egg‐laying stimulation (Figure E) and the unreceptiveness for a secondary mating (Figure H) is not sustained past the first 2 days post‐mating. This is similar to the PMR seen in mates of iab6 cocu mutant males who similarly also lack all VLCs in the SCs (Figure E) . Although the systematic functional analysis of rab11 was prevented due to general lethality using our driver, we were able to test for the effects of rab7 and rab19 knock‐down.…”

“…The association of specific Rabs to maturing VLCs begs the question of whether or not the Rabs are directly required for the formation of the VLCs and SC functionality. Previously, we have shown that the maintenance of the PMR is impaired in mutants that lack all VLCs . Here, we chose to individually knock‐down each candidate rab in SCs and to assay VLC appearance and the long‐term, female PMR.…”

“…Alternatively, Rab19‐VLCs could be secretory and simply are not required for the PMR. Previously, we have shown that the VLCs are not required to secrete some SFPs (including CG1656 and CG17575) to the lumen, but that these proteins are incorrectly modified in mutant backgrounds lacking the VLCs . Because loss of these proteins causes the same PMR phenotype as the lack of VLCs, it has been suggested that the modification of these proteins or other proteins with which these proteins interact is the cause of the PMR phenotype.…”

Identification and characterization of a new long noncoding RNA iab‐1 in the Hox cluster of silkworm, Bombyx mori identification of iab‐1

“…It represses the expression of abd‐ A in cis through the process of its transcription, which in turn, affects the activity of cis‐ regulatory elements of abd‐ A and produces a miRNA ( mir‐iab‐8 ) that is encoded by its intron and represses abd‐ A expression . Another lncRNA, msa , which shares much of its sequence with iab‐8 , is required for the development of the secondary cells of the Drosophila male accessory gland . To date, only a few functional aspects related to lncRNA have been reported in other insects.…”

“…17,18 Another lncRNA, msa, which shares much of its sequence with iab-8, is required for the development of the secondary cells of the Drosophila male accessory gland. 19 To date, only a few functional aspects related to lncRNA have been reported in other insects.…”