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Although the cell atlas of the human ocular anterior segment of the human eye was revealed by single‐nucleus RNA sequencing, whether subtypes of lens stem/progenitor cells exist among epithelial cells and the molecular characteristics of cell differentiation of the human lens remain unclear. Single‐cell RNA sequencing is a powerful tool to analyse the heterogeneity of tissues at the single cell level, leading to a better understanding of the processes of cell differentiation. By profiling 18,596 cells in human lens superficial tissue through single‐cell sequencing, we identified two subtypes of lens epithelial cells that specifically expressed C8orf4 and ADAMTSL4 with distinct spatial localization, a new type of fibre cells located directly adjacent to the epithelium, and a subpopulation of ADAMTSL4+ cells that might be lens epithelial stem/progenitor cells. We also found two trajectories of lens epithelial cell differentiation and changes of some important genes during differentiation. [ABSTRACT FROM AUTHOR]

The cover image is based on the Original Article Single‐cell RNA sequencing reveals new subtypes of lens superficial tissue in humans by Meng‐Chao Zhu et al., https://doi.org/10.1111/cpr.13477. [ABSTRACT FROM AUTHOR]

Previous studies have indicated that China is one of the domestication centres of Asian cultivated rice ( Oryza sativa), and common wild rice ( O. rufipogon) is the progenitor of O. sativa. However, the number of domestication times and the geographic origin of Asian cultivated rice in China are still under debate. In this study, 100 accessions of Asian cultivated rice and 111 accessions of common wild rice in China were selected to examine the relationship between O. sativa and O. rufipogon and thereby infer the domestication and evolution of O. sativa in China through sequence analyses of six gene regions, trn C-ycf6 in chloroplast genomes, cox3 in mitochondrial genomes and ITS, Ehd1, Waxy, Hd1 in nuclear genomes. The results indicated that the two subspecies of O. sativa (indica and japonica) were domesticated independently from different populations of O. rufipogon with gene flow occurring later from japonica to indica; Southern China was the genetic diversity centre of O. rufipogon, and the Pearl River basin near the Tropic of Cancer was the domestication centre of O. sativa in China. [ABSTRACT FROM AUTHOR]

The waxy protein primarily controls the synthesis of amylose, which is a key determinant of rice (Oryza sativa L.) cooking and processing qualities. Knowledge of the diversity of waxy gene in Chinese rice is essential to validate molecular markers for marker-assisted selection and to trace the origin of Chinese glutinous rice. The waxy (Wx) gene in the wild rice has rarely been studied, and the origin of Chinese glutinous rice is not well understood. The objectives of our investigation were (i) to identify the diversity of Wx and molecular markers for marker-assisted breeding and (ii) trace the origin of Chinese glutinous rice. We examined the sequence variations for the waxy gene of 98 accessions of cultivated rice and 134 accessions of wild rice from a previously established microcore collection of Chinese rice germplasm. A total of 51 and 226 single nucleotide polymorphisms (SNPs) or insertions or deletions were found in the cultivated rice and the wild rice, respectively. Wild rice accessions had much higher diversity than cultivated rice and nonglutinous rice had much higher diversity than glutinous rice whereas the genetic diversity of indica rice was similar to that of japonica rice. Polymorphisms of CTn microsatellite, G/T SNP, and 23-bp insertion in the waxy gene and their relationship to amylose content were explored using cultivated rice. The G/T allele and 23-bp insertion were better associated with amylose content than with the CTn alleles, and they were validated as molecular markers for markerassisted selection. All the wild rice accessions with 23-bp insertion or Τ allele came from South China and the glutinous rice originated from wild rice of South China parallel with indica and japonica differentiation. [ABSTRACT FROM AUTHOR]