Sugar transporters are essential for osmotic process regulation, various signaling pathways and plant growth and development.  Currently, few studies are available on the function of sugar transporters in sorghum (Sorghum bicolor L.).  In this study, we performed a genome-wide survey of sugar transporters in sorghum.  In total, 98 sorghum sugar transporters (SSTs) were identified via BLASTP.  These SSTs were classified into three families based on the phylogenetic and conserved domain analysis, including six sucrose transporters (SUTs), 23 sugars will eventually be exported transporters (SWEETs), and 69 monosaccharide transporters (MSTs).  The sorghum MSTs were further divided into seven subfamilies, including 24 STPs, 23 PLTs, two VGTs, four INTs, three pGlcT/SBG1s, five TMTs, and eight ERDs.  Chromosomal localization of the SST genes showed that they were randomly distributed on 10 chromosomes, and substantial clustering was evident on the specific chromosomes.  Twenty-seven SST genes from the families of SWEET, ERD, STP, and PLT were found to cluster in eight tandem repeat event regions.  In total, 22 SSTs comprising 11 paralogous pairs and accounting for 22.4% of all the genes were located on the duplicated blocks.  The different subfamilies of SST proteins possessed the same conserved domain, but there were some differences in features of the motif and transmembrane helices (TMH).  The publicly-accessible RNA-sequencing data and real-time PCR revealed that the SST genes exhibited distinctive tissue specific patterns.  Functional studies showed that seven SSTs were mainly located on the cell membrane and membrane organelles, and 14 of the SSTs could transport different types of monosaccharides in yeast.  These findings will help us to further elucidate their roles in the sorghum sugar transport and sugar signaling pathways.

Patatin-like phospholipase domain containing 5 (PNPLA5) is a neotype neutral lipase with dual activity of anabolism and catabolism in vitro and in vivo, which has a low mRNA expression level in humans and mice.  PNPLA5, which is localized to lipid droplets and required for efficient autophagy by optimal initiation, has been speculated to possess triglyceride hydrolase activity, and has been associated with low density lipoprotein cholesterol (LDL-C).  Above all, PNPLA5 is a relatively new gene, which is reported less about its biological function research, especially the function research in the rats is still blank.  In this study, we examined the spatiotemporal expression profile of PNPLA5 and found that it was expressed at low levels in most organs of Sprague Dawley (SD) rats, but was present at very high levels in the skin and testes.  To further determine the biological function of PNPLA5 in mammals, we generated PNPLA5-knockout SD rats using the clustered regularly-interspaced short palindromic repeats (CRISPR)/Cas9 system.  PNPLA5-null rats were viable, but showed a variety of phenotypic abnormalities, such as abnormal bleeding, and varied hematobiochemical parameters including increased serum total cholesterol (TC), triglycerides and high density lipoprotein cholesterol (HDL-C) level, and reduced LDL-C level, compared with wild-type control rats.  These data are consistent with an important role for PNPLA5 in lipid metabolism, providing a new target gene and animal model for treatment of cardiovascular diseases in the future.