Effect of Temperature in the Transcriptomic Profile of Octopus maya Optic Glands

Octopus maya is an endemic species of the Yucatan Peninsula where is the base of an important fishery. Their habitat is subject to significant climatic variations throughout the year; hence, the reproduction is under a specific thermal stimulus. Previous work showed that reproduction is favored at 24 °C, while at 30 °C the production of gametes in males and females, as well as the reproductive success of the species is see committed. In a global warming scenario, the increase in the temperature of the ocean could have severe implications on the reproductive process of O. maya population. It has been proposed that the optic glands (OG) contain factors associated with the control of reproductive aspects such as sexual maturation, reproductive behavior, feeding, and parental care. In order to describe the molecular mechanisms involved in the regulation of reproduction, the transcriptomic profiles of the optic gland from both genders of O. maya were obtained by sequencing paired-end cDNA libraries using Illumina MiSeq platform. Males and females were exposed to different temperatures (24 °C and 30 °C) for 30 d. After thermal exposure, the organisms were mated with octopus maintained at a preferred temperature. For males, two reproductive conditions were evaluated (PRE and POST mating) meanwhile for females samples were taken before, during, and after spawning (PRE. SPAWN, POST). RNA-seq analysis generated 320,187,525clean paired-end reads, which were assembled into 242,896 transcripts. The differential expression analysis revealed a sexual dimorphism between male and female transcriptomic profiles. This is, for males, the enrichment processes were biological regulation, behavior, and signal transduction with no differences before and after mating. For females, processes associated with transcriptional dysregulation and oxidative stress are enriched during the three conditions analyzed, suggesting similar expression patterns associated with neurodegenerative diseases.