The Function Study On CD133 In The Development Of Mouse Neural Retina

CD133 is a five-time transmembrane cholesterol-binding glycoprotein that is often used as a specific marker for human hematopoietic stem and progenitor cells,neural stem cells,and cancer stem cells.In the retina,CD133 is localized to the inner and outer segments of the cone and rod cells,the retinal pigment epithelium of the fetal mouse,and the inner nuclear layer of the adult mouse retina.CD133 gene mutation or allelic deletion will lead to photoreceptor cell disk membrane and outer segment distortion,which will cause various degrees of progressive visual deterioration,myopia,color vision abnormalities and night vision difficulties,causing macular degeneration,Stargardt like macular dystrophy,cone-rod dystrophy and retinitis pigmentosa and other diseases.Therefore,the role of CD133 in the development of mouse retina is important for the study of retinal-related diseases.In this study,CD133-CreERT2 transgenic mice and C57BL/6 mice were used as experimental materials.Fluorescence staining and and hematoxylin and eosin staining were used to study morphological differences in retina of CD133 homozygous mutant mice(CD133-/-),CD133 heterozygous mutant mice(CD133+/-)and wild type mice(WT)at different developmental stages(postnatal day 1,8,14,20 and 30).The transcriptome sequencing technology was used to obtain the sequencing data of three types of mouse retinas at different developmental stages(postnatal day 15 and 30).And bioinformatics techniques such as differentially expression genes and weighted gene co-expression network analysis were used to comprehensively compare three types of mouse retinas in biological characteristics from transcriptome levels.Through morphological study,we found that when the CD133 gene is homozygously deleted,the mouse retina appears morphological abnormality at the early stage(postnatal day 20).The main manifestation is that the outer nuclear layer of the retina becomes thinner,and the inner and outer segments of photoreceptor cells become shorter.When the CD133 gene is heterozygously deleted,the mouse retina has morphological abnormalities in the late stage(postnatal day 30),which mainly shows that the inner and outer segments of the photoreceptor cells become short,andthe outer nuclear layer of the retina has no obvious abnormalities.The transcriptome study found that when the CD133 gene is homozygously deleted of mouse,the retinal-related gene expression was down-regulated in the early stage(postnatal day15),the expression of inflammation-related genes was up-regulated and the expression of retinal-related functional genes was down-regulated at postnatal day30.When the CD133 gene is heterozygously deleted,the mouse retina exhibits downregulation of retinal-related functional gene expression at different stages(postnatal day 15 and 30).In conclusion,our study found that CD133 gene is involved in the morphology and function of retinal photoreceptor cells;it was first confirmed from the transcriptome level that deletion of CD133 gene can cause abnormal morphology and function of retinal photoreceptor cells,and then secondary inflammation of the retina.We initially explored the molecular mechanism of interaction with CD133.This provides a scientific basis for studying the mechanism of retinal diseases and provides new ideas for the treatment of retinal diseases.