Identification of Splicing Variation Associated with Parental Behavior in the Burying Beetles (Nicrophorus orbicollis).

Abstract

The molecular basis of parental behavior in burying beetles is not well understood. This study is a first attempt to evaluate the extent of alternative splicing (AS) as a source of transcriptome diversity that may facilitate flexible parenting behavior in this species. RNA-seq datasets from beetle parents exhibiting high or low care behavior and a newly available Nicrophorus orbicollis genome were used to perform AS analysis by AStalavista to comprehensively classify AS events, and specific patterns of splicing variation within and across parental groups were evaluated. Towards functional characterization, AS genes were annotated via protein family analysis. Transcriptome-wide AS profiles for each parental group were established, revealing no specific splicing patterns associated with either sex or parenting phenotype (high or low care behavior). Among simple types of AS events, intron retention was the most common (13%), while mutually exclusive exons were the least common (0.4%), with alternative acceptor (6%) and alternative donor (5%) occurring slightly more often than exon skipping (3%). Functional annotation highlighted AS genes belonging to protein families broadly linked to chemoreception, neuromodulation and JH function, all biological processes essential for the regulation of reproductive behavior and physiology. This analysis was successful in generating a large catalogue of AS events associated with parenting behavior in burying beetles. Additional analyses could expand upon this dataset to include tissue, development and species-specific splice variants, as well as functionally validate AS transcripts via RT-PCR to further clarify the role of functional AS in behavioral regulation in this species.