Effects of Luteinizing Hormone‐releasing Hormone Analog Injection on Intestinal Transcriptome in Grass Carp, Ctenopharyngodon idella

The present study aimed to detect the changes in gene expression by luteinizing hormone‐releasing hormone analog (LHRH‐A) stimulation in the intestine of grass carp. LHRH‐A has been widely used for inducing ovulation of teleosts. The transcriptome changes induced by LHRH‐A are not fully understood, especially in intestines. To understand the changes of RNA expression after intraperitoneal injection of LHRH‐A, two cDNA libraries of intestines from grass carps, including LHRH‐A injection group and control group, were sequenced using Illumina HiSeq 4000 (Illumina, San Diego, CA, USA). In total, 13,581,225,000 nucleotides were obtained and 66,127 unigenes were generated by de novo assembly. The differentially expressed genes were identified by comparing the Fragments Per Kilobase Of Exon Per Million of the unigenes between the two groups. The results indicated that 255 and 212 unigenes were upregulated and downregulated, respectively, in the LHRH‐A injection group. Furthermore, the protein digestion and absorption pathways as well as fat digestion and absorption pathways tended to be upregulated by LHRH‐A injection. These findings provide a valuable resource for understanding the response of intestinal transcriptome levels to hormones.