Chromosome-level genome assemblies ofChanna argusandChanna maculataand comparative analysis of their temperature adaptability

Abstract

Background Channa argus and Channa maculata are the main cultured species of the snakehead fish family, Channidae. The relationship between them is close enough that they can mate; however, their temperature adaptability is quite different. Results In this study, we sequenced and assembled the whole genomes of C. argus and C. maculata and obtained chromosome-level genome assemblies of 630.39 and 618.82 Mb, respectively. Contig N50 was 13.20 and 21.73 Mb, and scaffold N50 was 27.66 and 28.37 Mb, with 28,054 and 24,115 coding genes annotated for C. argus and C. maculata, respectively. Our analyses showed that C. argus and C. maculata have 24 and 21 chromosomes, respectively. Three pairs of chromosomes in C. argus correspond to 3 chromosomes in C. maculata, suggesting that 3 chromosomal fusion events occurred in C. maculata. Comparative analysis of their gene families showed that some immune-related genes were unique or expandable to C. maculata, such as genes related to herpes simplex infection. Analysis of the transcriptome differences related to temperature adaptation revealed that the brain and liver of C. argus rapidly produced more differentially expressed genes than C. maculata. Genes in the FoxO signalling pathway were significantly enriched in C. argus during the cooling process (P < 0.05), and the expression of 3 transcription factor genes in this pathway was significantly different between C. argus and C. maculata (P < 0.01). Conclusions C. maculata may have higher resistance to certain diseases, whereas C. argus has a faster and stronger response to low-temperature stress and thus has better adaptability to a low-temperature environment. This study provides a high-quality genome research platform for follow-up studies of Channidae and provides important clues regarding differences in the low-temperature adaptations of fish.

Molecular Characteristics, Expression Patterns, and Response of Insulin-like Growth Factors Gene Induced by Sex Steroid Hormones in Blotched Snakehead (Channa maculata)

“…In the present study, IGFs, which are known to be involved in growth regulation, were characterized in blotched snakehead (C. maculata). Consistent with findings in zebrafish (D. rerio) [9] and giant grouper (E. lanceolatus) [16], two copies of IGF1 were identified in blotched snakehead, designated as CmIGF1-1 and CmIGF1-2, located on chromosomes 15 and 10, respectively [30]. The IGF1 gene in many fish species, including giant grouper (E. lanceolatus) [16], ussuri catfish (Pseudobagrus ussuriensis) [34], and zebrafish (D. rerio) [9], typically consists of five exons and four introns, with intron 2 being the longest.…”

“…Full-Length cDNA Cloning and Sequence Analysis for IGFs in Blotched Snakehead (C. maculata) Three IGF genes were identified in the blotched snakehead genome (SRA Accession No. PRJNA730430) [30]. Primers were specifically designed to verify the predicted cDNA sequences.…”

“…The gDNA was extracted from fin tissues using the General AllGen Kit (CWBio, Taizhou, China) following the manufacturer's protocol. Specific primers (Table 2) were designed according to the predicted genome sequences of IGFs obtained from the blotched snakehead genome [30]. Subsequently, the genomic sequences of CmIGFs were amplified using these primers and the fin gDNA as the template.…”

Targeting autophagy with natural products as a potential therapeutic approach for diabetic microangiopathy

“…The FOXO transcription factor family regulates various cellular physiological processes such as apoptosis, glucose metabolism, oxidative stress resistance, and lifespan extension ( Ou et al, 2021 ). FOXO1 and FOXO3 are the most widely utilized members of the FOXO family, which can combine with promoter regions to activate autophagy genes such as Vps34, Beclin-1 and Rab7 ( Ferdous et al, 2010 ; Webb and Brunet, 2014 ).…”

Comparison of nutritional value of snakehead fish from Guangdong and Deqing varieties

“…Snakehead fish ( Channa argus ), commonly known as black fish, is a fierce carnivorous animal distributed in rivers, lakes and ponds. It is largely found in various water systems of India, Southeast Asia, Russia, Korea and Japan [ 1 , 2 ]. Especially, China has the large distribution, mainly found in the Yangtze River basin.…”