Meeting Abstract
Viviparous reproduction is characterized by maternal retention of developing offspring within her reproductive tract during gestation, culminating in live birth. In some cases a mother will provide nutrition beyond that present in the yolk; this is known as matrotrophic viviparity. While this phenomenon is best associated with mammals, it is observed in insects such as the viviparous cockroach, Diploptera punctata. Female D. punctata carry developing embryos in the brood sac, a reproductive organ that acts as both a uterus and placenta by providing a nutritive milk-like secretion to the intrauterine developing progeny. While the basic physiology of milk secretion has been characterized, little is known about the underlying molecular mechanisms of D. punctata pregnancy. This study utilizes RNA-seq analysis to characterize transcriptional changes associated with D. punctata pregnancy and provides the first transcriptome for this species. Following de novo contig assembly, a comparison of four stages of the female reproductive cycle (mated but not pregnant, pre lactation pregnancy, early lactation pregnancy, and late lactation pregnancy) along with a male-female comparison revealed unique transcriptional profiles corresponding to each stage. Differentially regulated transcripts of interest include the previously identified family of milk proteins, transcripts associated with juvenile hormone metabolism, and other reproduction-associated transcripts. Further examination of differentially expressed transcripts will likely reveal novel molecular mechanisms underlying D. punctata reproduction.
