Diapause-Linked Gene Expression Pattern and Related Candidate Duplicated Genes of the Mountain Butterfly Parnassius glacialis (Lepidoptera: Papilionidae) Revealed by Comprehensive Transcriptome Profiling

Abstract

The mountain butterfly Parnassius glacialis is a representative species of the genus Parnassius, which probably originated in the high-altitude Qinhai–Tibet Plateau in the Miocene and later dispersed eastward into relatively low-altitude regions of central to eastern China. However, little is known about the molecular mechanisms underlying the long-term evolutionary adaptation to heterogeneous environmental conditions of this butterfly species. In this study, we obtained the high-throughput RNA-Seq data from twenty-four adult individuals in eight localities, covering nearly all known distributional areas in China, and firstly identified the diapause-linked gene expression pattern that is likely to correlate with local adaptation in adult P. glacialis populations. Secondly, we found a series of pathways responsible for hormone biosynthesis, energy metabolism and immune defense that also exhibited unique enrichment patterns in each group that are probably related to habitat-specific adaptability. Furthermore, we also identified a suite of duplicated genes (including two transposable elements) that are mostly co-expressed to promote the plastic responses to different environmental conditions. Together, these findings can help us to better understand this species’ successful colonization to distinct geographic areas from the western to eastern areas of China, and also provide us with some insights into the evolution of diapause in mountain Parnassius butterfly species.

Dispersal from the Qinghai-Tibet plateau by a high-altitude butterfly is associated with rapid expansion and reorganization of its genome

“…The homolog method was carried out using the software GeMoMa v1.3.1 72 with default parameters. Transcriptome sequences of 6 adult individuals (muscle isolated from thorax) for two P. glacialis populations (BQXL and BQTM) were downloaded from the NCBI SRA database (Table S2 ) 73 . Transcript assembly and expression analysis based on the reference genome were performed using Hisat v2.0.4 (-max-intronlen 20000, -min-intronlen 20) 74 , Stringtie v1.2.3 (with default parameters) 75 .…”

Host genetics and larval host plant modulate microbiome structure and evolution underlying the intimate insect–microbe–plant interactions in Parnassius species on the Qinghai‐Tibet Plateau

“…The genus Parnassius is a typical alpine butterfly group, mainly distributed across the Holarctic, with its highest diversity on the Qinghai‐Tibet Plateau (QTP) and adjacent mountainous regions (including Xinjiang and Gansu, China). The majority of species in this genus often occur in sympatry and the same species could colonize at different localities, across a broad elevational range 2800–5200 m above sea level (Chou, 1994 ; Su et al., 2023 ; Wu, 2001 ). However, a few species also can secondarily colonize at relatively low‐altitude habitats, such as Parnassius glacialis , mainly distributed at about 200–1800 m above sea level in central‐to‐southeastern China.…”