Generation And Gene Expression Analysis Of Rab39b Knockout Mice

Background and objective:Rab family proteins play an important role in the regulation of vesicle transport.Mutations in certain Rab proteins have been found to cause diseases.More than 60 human Rab family proteins have been identified so far,but the physiological functions of many Rab proteins remain unknown.As a member of the Rab family,RAB39B is specifically expressed in neurons.Although cellular research suggests that RAB39B plays a role in the process of neuronal membrane protein transport and participates in the formation and maintenance of synapses,and that RAB39B may also be involved in autophagy,the exact function of RAB39B,especially at the animal level,is unclear.Recent studies have found that mutations in the RAB39B gene are closely related to X chromosome related intellectual disability,Parkinson's disease and autism.Therefore,it is urgent to reveal the physiological and pathological functions of RAB39B,so as to provide clues for disease pathogenesis treatment.Methods and Results:In this study,we used TALEN technology to construct Rab39b knockout mice,and confirmed that there was no RAB39B protein expression in these mice.Preliminary observation showed that Rab39b knockout mice could be born normally without apparent defects in appearance.We further applied RNA-seq to study the effect of Rab39b gene deletion on the expression of other genes in the brain.The results identified 30 significantly up-regulated genes and 31 significantly downregulated genes.Most of these genes are non-protein-encoding RNAs,and only 9 are known protein-encoding genes.Gene Ontology analysis showed that these affected genes might participate in cell membrane and organelle structure in the cell,be involved in location during the biological process,and have binding,catalysis and transport functions.KEGG analysis suggested that these genes might be involved in diseases such as tumor,immunity,infection,and that they also participate in metabolism.However,when we carried out corroboration test on the expression of the 9 affected protein-encoding genes,we only confirmed that the expression of Hist2h3c1 did decrease in Rab39b gene knockout mice.Conclusions:These results suggest that the deletion of Rab39b has no marked influence on the expression of protein encoded genes,and RAB39B might affect the function of other proteins more at the protein-protein interaction level.Our study on the construction of Rab39b knockout mice and preliminary analysis of gene expression in these mice lays a foundation for further revealing the physiological function and pathological role of RAB39B.