Study On The Photosensitivity And Color Discrimination Ability Of The Silver Star Bamboo Rat

Rhizomys pruinosus is a typical subterranean rodents which belong to the genus Rhizomys family of Rodentia,Spalacidae,Rhizomyinae,Rhizomys.It is a typical underground mouse which live underground cave for lifetime.In order to adapt to the dark environment of the underground,the visual system has developed a series of adaptation mechanisms during the evolution process.It is an ideal model animal for studying the sensitivity and color discrimination of subterranean rodents.In the underground dark caves,the sensitization and color discrimination of the subterranean rodent will be adapted accordingly.At present,the morphology,behavioral and physiological and biochemical indexes of the Hoary Bamboo Rat have been studied,but little research has been done on the sensitization and color discrimination ability of the Hoary Bamboo Rat.Studies have shown that the eyes of the species of the Cryptomys are small but sensitive,and the eyes of Zambia Spalax ehrenbergi and the Spalax ehrenbergi have no visual ability,and strong flashes can not cause behavioral responses,but they have the ability to sense photoperiod,therefore,it is of great significance to study the sensitization of the visual system of the Hoary Bamboo Rat under different illumination conditions.In this study,transcriptome sequencing of Hoary Bamboo Rat sights under different shades of light,natural light,red light,green light and blue light,and different illumination durations,bioinformatics analysis of sequencing results,simultaneous functional annotation and differential expression Gene screening and GO annotation and KEGG pathway analysis of differentially expressed genes.The genes related to sensitization and color discrimination were excavated at the molecular level.Combined with Real-Time PCR technology,the CYP2B1,CYP2C55,CYP3A9,CYP4A12 and ADH genes related to the sensitization of Hoary Bamboo Rat were analyzed.The aim is to explore the sensitization and color discrimination ability of the visual system of the Hoary Bamboo Rat,and lay a foundation for the study of the sensitization and color discrimination mechanism of the subterranean rodents.The main results and conclusions are as follows:1.A total of 189.18Gb Clean Data was obtained from the transcriptome sequencing of the Hoary Bamboo Rat.The number of clean reads of each sample was not less than 21,193,335.The Trinity software was used to splice the obtained clean reads from scratch,and a total of 106,606 Transcripts were obtained.The longest transcript in each gene was used as Unigene for subsequent annotation analysis.A total of 48,119 Unigenes were obtained,indicating good assembly integrity.Using BLAST software to compare Unigene sequences with NR,Swiss-Prot,GO,COG,KOG,eggNOG,Pfam.KEGG databases,and obtain 16,526 Unigene annotation results,enriching the gene database of Hoary Bamboo Rat and providing the foundation for further visual correlation Genes.The CDS of all Unigene transcriptomes were blast-aligned in the NR,Swiss-Prot,KEGG and COG databases to obtain 34,418 CDS sequence fragments.SNP analysis showed that there were a large number of SNPs in the transcriptome,and the number of SNPs that were transformed and transposed was 210,962 and 83,030,respectively,accounting for 71.76%and 28.24%.Based on the gene structure analysis of the Unigene library,SSR analysis obtained 16036 intact SSR markers.In the NR classification,the number of Unigenes with similarities in the known genes of 10 species of Hoary Bamboo Rat,such as Spalax ehrenbergi,Homo sapiens,and Sus scrofa,accounted for 85.29%of the total number of Unigenes annotated in the NR database.Among them,the Spalax ehrenbergi has the highest similarity.2.After different light treatments,the differential gene expression analysis of the spectacles of the Hoary Bamboo Rat,the GO and KEGG annotations were performed on the differentially expressed genes,and the GO annotation results were mainly annotated into three major categories:biological processes,cellular components and molecular functions.Pathway analysis using KEGG Pathway showed that differential genes were mainly annotated into Retinol metabolism,Circadian entrainment,and Calcium signaling pathway,and the main metabolic pathway was the Retinol metabolism.The pathway is annotated in natural light 75 min VS red light 75 min,natural light 75 min VS green light 75 min and natural light 75 min VS blue light 75 min group.Through KEGG analysis,natural light 75minVS red light 75min enriched to 194 pathways,natural light 75minVS green light 75min enriched to 165 pathways,natural light 75minVS blue light 75min enriched to 111 pathways,these three groups compare the path to the annotation more,it can be seen that with the extension of illumination time,the influence of different color light illumination on the Hoary Bamboo Rat is also gradually strengthened,which leads to the initiation or alteration of certain metabolic pathways in the body.3.The expression of CYP2B1 under red light was up-regulated compared with other treatment groups,and the difference was significant,indicating that red light contributes to the expression of CYP2B1 and CYP2B1 participates in retinoic acid metabolism,can decompose all-trans retinoic acid into 4-oxo-all-trans retinoic acid,all-trans-18-hydroxy-retinoic acid and all-trans-5,6 epoxy Retinoid,As a result,the retinoic acid content is reduced,which further leads to a decrease in the content of retinal of the photosensitive pigment component,indicating that the Hoary Bamboo Rat responds to red light exposure and can feel red light.4.In the Hoary Bamboo Rat,under the treatment of 1 min,the expression of CYP2C55 was significantly up-regulated compared with dark,natural light,red light and blue light.It can be seen that green light can promote the expression of CYP2C55 and contributes to the breakdown of all-trans retinoic acid under short-time illumination Under the treatment of 75 min,the expression of CYP2C55 was decreased compared with dark,natural light,red light and blue light,indicating that green light contributes to the storage of all-trans retinoic acid under prolonged illumination.From the above results,it can be seen that the Hoary Bamboo Rat responds to the green light exposure and can feel the green light.5.Under the 1 min and 75 min illumination treatments,the expression of CYP3A9 was significantly different between the dark and natural light treatment groups,indicating that the Hoary Bamboo Rat have photosensitivity.CYP3A9 catalyzes the various stages of vitamin A metabolism,which can decompose all-trans retinoic acid into 4-oxo-all-trans retinoic acid,all-trans-18-hydroxy-retinoic acid and all-trans-5,6 epoxy Retinoid,resulting in a decrease in retinoic acid.Compared with other treatment groups,the expression of CYP3A9 was significantly up-regulated in the natural light treatment group at 1 min and 75 min illumination,indicating that the Hoary Bamboo Rat responded to natural light exposure and had the ability to feel natural light.6.In the Hoary Bamboo Rat,the expression of CYP4A12 in the natural light,red light,green light and blue light treatment groups was up-regulated compared with the dark treatment group at 1 min and 75 min light treatment.CYP4A12 can metabolize all-trans retinoic acid to all-trans-18-hydroxy-retinoic acid,resulting in a decrease in all-trans retinoic acid,which affects the content of all-trans retinal,indicating that the Hoary Bamboo Rat responds to light,Compared with other treatment groups,the expression of CYP4A12 was significantly up-regulated under natural light at 75min light treatment,indicating that the Hoary Bamboo Rat responded to natural light exposure and could feel natural light.7.Under the 1 min illumination treatment,the expression of ADH was down-regulated under blue light compared with other treatment groups.It indicates that the Hoary Bamboo Rat responds to blue light exposure and can feel blue light.Under 75 min light treatment,the expression of ADH was significantly up-regulated under natural light,red light,green light and blue light compared to the dark treated group.ADH is the main enzyme for retinoic acid synthesis.Retinoic acid plays an important role in visual maintenance.It eventually reaches the nucleus and binds to retinoic acid receptor,thereby initiating or inhibiting gene transcription and exerting biological effects.It can be seen that the Hoary Bamboo Rat responds to light and has photosensitivity.From the above results,it can be seen that the Hoary Bamboo Rat has a sensitizing ability and responds to the illumination of different color lights,indicating that the Hoary Bamboo Rat can feel different color light.