The SWEET (sugars will eventually be exported transporter) family was identified as a new class of sugar transporters that function as bidirectional uniporters/facilitators and facilitate the diffusion of sugars across cell membranes along a concentration gradient. SWEETs are found widely in plants and play central roles in many biochemical processes, including the phloem loading of sugar for long-distance transport, pollen nutrition, nectar secretion, seed filling, fruit development, plant–pathogen interactions and responses to abiotic stress. This review focuses on advances of the plant SWEETs, including details about their discovery, characteristics of protein structure, evolution and physiological functions. In addition, we discuss the applications of SWEET in plant breeding. This review provides more in-depth and comprehensive information to help elucidate the molecular basis of the function of SWEETs in plants.

cabbage (Brassica oleracea var. capitata) is an important vegetable crop widely grown throughout the world, providing plentiful nutrients and health-promoting substances. To facilitate further genetics and genomic studies and crop improvement, we present here a high-quality reference genome for cabbage. We report a de novo genome assembly of the cabbage double-haploid line D134. A combined strategy of single-molecule real-time (SMRT) sequencing, 10× Genomics and chromosome conformation capture (Hi-c) produced a high quality cabbage draft genome. the chromosome-level D134 assembly is 529.92 Mb in size, 135 Mb longer than the current 02-12 reference genome, with scaffold N50 length being raised as high as 38 times. We annotated 44,701 high-quality protein-coding genes, and provided full-length transcripts for 45.59% of the total predicted gene models. Moreover, we identified novel genomic features like underrated TEs, as well as gene families and gene family expansions and contractions during B. oleracea evolution. The D134 draft genome is a cabbage reference genome assembled by SMRT long-read sequencing combined with the 10× Genomics and Hi-C technologies for scaffolding. This high-quality cabbage reference genome provides a valuable tool for improvement of Brassica crops. Brassica oleracea is an important vegetable species widely grown throughout the world. The species comprises several subspecies showing extensive morphological and phytochemical diversity. As a diploid species, B. oleracea underwent a whole-genome triplication (WGT) event 1 , followed by two whole-genome duplication (WGD) event 2,3 and a specific WGT 4 of the Brassiceae lineage, thus becoming a model for studies on polyploid genome evolution. Currently, two B. oleracea genomes based on next-generation sequencing (NGS) technology are available: the TO1000 (kale-like; B. oleracea var. alboglabra) assembly and the 02-12 (cabbage; B. oleracea var. capitata) assembly 5,6 , but their errors and gaps make them difficult to use for many studies 7-10. Recently, B. oleracea L. var. italica (broccoli) genome assembly was completed using long reads and optical maps 11. Broccoli and cabbage belong to Brassica species, however their growth, morphology and molecular levels is extremely variable, showing the importance of generating several genome assemblies for different morphotypes of B. oleracea. Up to now, there is still no high quality, comprehensive assembled cabbage (B. oleracea var. capitata) genome, which hinders greatly basic genetics and genomics research, as well as crop improvement. Thus generating an accurate cabbage genome assembly is crucial. To obtain a homozygous genome, the cabbage double-haploid (DH) line D134 was produced by microspore culture. We conducted whole-genome sequencing and de novo assembly for this line using single-molecule realtime (SMRT) cells on a PacBio Sequel platform combined with high-throughput chromosome conformation capture (Hi-C), next generation sequencing (NGS) and 10× Genomics technologies. This genome assembly is...

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