Molecular and evolutionary mechanisms of self-incompatibility in angiosperms.

As an intraspecific outcrossing mechanism, self-incompatibility (SI) widely adopted by hermaphroditic plants is usually controlled by a polymorphic multi-allelic S locus. Typically, six molecular types of SI have been found, including type-I controlled by the pistil S S-RNase and pollen S SLFs commonly spread in Plantaginaceae, Solanaceae, Rosaceae and Rutaceae, type-II by SRK and SCR in Brassicaceae, type-III by PrsS and PrpS in Papaveraceae, type-IV by CYP-GLO2-KFB-CCM-PUM in Primulaceae, type-V by TsSPH1-TsYUC6-TsBAHD in Turneraceae and type-VI by HPS10-S and DUF247I-S in Poaceae, with type-I characterized as a non-self recognition system but types-II, -III and -VI self ones. Furthermore, remarkable progresses have been made in their origin and evolutionary mechanisms recently. Among them, type-I SI possessed a single origin in the most recent common ancestor of eudicots and types II-V dynamically evolved following its losses, while type-VI SI exclusively existed in monocot Poaceae may be regained after the loss of the ancient type-I. Here, we mainly review the molecular and evolutionary mechanisms of angiosperm SI systems, thus providing a helpful reference for their theoretical research and breeding application.

The 2019 novel coronavirus resource.

An ongoing outbreak of a novel coronavirus infection in Wuhan, China since December 2019 has led to 31,516 infected persons and 638 deaths across 25 countries (till 16:00 on February 7, 2020). The virus causing this pneumonia was then named as the 2019 novel coronavirus (2019-nCoV) by the World Health Organization. To promote the data sharing and make all relevant information of 2019-nCoV publicly available, we construct the 2019 Novel Coronavirus Resource (2019nCoVR, https://bigd.big.ac.cn/ncov). 2019nCoVR features comprehensive integration of genomic and proteomic sequences as well as their metadata information from the Global Initiative on Sharing All Influenza Data, National Center for Biotechnology Information, China National GeneBank, National Microbiology Data Center and China National Center for Bioinformation (CNCB)/National Genomics Data Center (NGDC). It also incorporates a wide range of relevant information including scientific literatures, news, and popular articles for science dissemination, and provides visualization functionalities for genome variation analysis results based on all collected 2019-nCoV strains. Moreover, by linking seamlessly with related databases in CNCB/NGDC, 2019nCoVR offers virus data submission and sharing services for raw sequence reads and assembled sequences. In this report, we provide comprehensive descriptions on data deposition, management, release and utility in 2019nCoVR, laying important foundations in aid of studies on virus classification and origin, genome variation and evolution, fast detection, drug development and pneumonia precision prevention and therapy.

An online coronavirus analysis platform from the National Genomics Data Center.

Since the first reported severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in December 2019, coronavirus disease 2019 (COVID-19) has become a global pandemic, spreading to more than 200 countries and regions worldwide. With continued research progress and virus detection, SARS-CoV-2 genomes and sequencing data have been reported and accumulated at an unprecedented rate. To meet the need for fast analysis of these genome sequences, the National Genomics Data Center (NGDC) of the China National Center for Bioinformation (CNCB) has established an online coronavirus analysis platform, which includes de novoassembly, BLAST alignment, genome annotation, variant identification, and variant annotation modules. The online analysis platform can be freely accessed at the 2019 Novel Coronavirus Resource (2019nCoVR) (https://bigd.big.ac.cn/ncov/online/tools).

[Generation of chemical-inducible activation tagging T-DNA insertion lines of Arabidopsis thaliana].

Using an estrogen-inducible expression XVE (LexA-VP16-Estragon Receptor) system, we have generated approximately 40 000 independent T-DNA insertion lines of Arabidopsis thaliana. Segregation analyses of about 18000 lines indicated that 51.6% of them contain single T-DNA insertions and that the average insertion number is 1.38 copies per line. Mutants displaying a variety of morphological alterations were identified, including those that affect development of roots,hypocotyls, leaves, floral organs and seeds as well as the flowering time.

[The thirty years of Acta Genetica Sinica].

Acta Genetica Sinica (AGS) is sponsored by the Genetics Society of China and the Institute of Genetics and Developmental Biology of Chinese Academy of Sciences, and is published by Science Press. The journal is a leading national academic periodical and one of the Chinese key periodicals of natural sciences. Currently, AGS is being indexed by several well-known domestic and international indexing systems, such as the American Chemical Digest (CA), BIOSIS database, Biological Digest (BA), Medical Index and Russian Digest (P [symbol: see text]). Papers in the areas of genetics, developmental biology, cell molecular biology and evolution are regularly published by AGS.

[Towards the positional cloning of a spikelet identity gene frizzle panicle (FZP) in rice (Oryza sativa L.)].

FZP is a key gene for spikelet differentiation in rice. Mutation of the gene blocks the differentiation of spikelets and makes rachis branches develop unlimitedly. A mutant of the gene named frizzle panicle (fzp) was previously found from the high-generation progeny of a cross between two Oryza sativa ssp. indica rice varieties, V20B and Hua1B. With the mutant, FZP had been mapped to a chromosomal region of about 26.4 cM in width between two SSR (Simple Sequence Repeat) markers, RM172 and RM18, on chromosome 7. In this study, high-resolution mapping of the gene was carried out for the positional cloning of the gene. Two flanking SSR markers, NRM6 and NRM8, were identified, which are 0.2 cM and 1.0 cM apart from the target gene, respectively, bracketing the target gene within an interval of 1.2 cM or 144 kb. An APETALA2 (AP2)-domain like gene was found at the expected position of FZP. As AP2 is known to play an important role in the floral development, we took it as the most possible candidate of FZP. PCR analysis showed that the mutant allele of the AP2-domain like gene contains an insert of about 4 kb in length, suggesting that the gene is very likely FZP.

A novel C2-domain phospholipid-binding protein, OsPBP1, is required for pollen fertility in rice.

Pollen fertility is a crucial factor for successful pollination and essential for seed formation. Recent studies have suggested that a diverse range of internal and external factors, signaling components and their related pathways are likely involved in pollen fertility. Here, we report a single C2-domain containing protein, OsPBP1, initially identified through cDNA microarray analysis. OsPBP1 is a single copy gene and preferentially expressed in pistil and pollen but down-regulated by pollination. OsPBP1 had a calcium concentration-dependent phospholipid-binding activity and was localized mainly in cytoplasm and nucleus, but translocated onto the plasma membrane in response to an intracellular Ca(2+) increase. Pollen grains of antisense OsPBP1 transgenic lines were largely nonviable, germinated poorly in vitro and of low fertility. OsPBP1 protein was localized in a region peripheral to pollen wall and vesicles of elongating pollen tube, and its repressed expression reduced substantially this association and led to alteration of microfilament polymerization during pollen germination. Taken together, these results indicate that OsPBP1 is a novel functional C2-domain phospholipids-binding protein that is required for pollen fertility likely by regulating Ca(2+) and phospholipid signaling pathways.