Genome diversity and highland-adaptative variation in Tibet barley landrace population of China.

Barley landraces accumulated variation in adapting to extreme highland environments during long-term domestication in Tibet, but little is known about their population structure and genomic selection traces. In this study, tGBS (tunable genotyping by sequencing) sequencing, molecular marker and phenotypic analyses were conducted on 1,308 highland and 58 inland barley landraces in China. The accessions were divided into six sub-populations and clearly distinguished most six-rowed, naked barley accessions (Qingke in Tibet) from inland barley. Genome-wide differentiation was observed in all five sub-populations of Qingke and inland barley accessions. High genetic differentiation in the pericentric regions of chromosomes 2H and 3H contributed to formation of five types of Qingke. Ten haplotypes of the pericentric regions of 2H, 3H, 6H and 7H were further identified as associated with ecological diversification of these sub-populations. There was genetic exchange between eastern and western Qingke but they shared the same progenitor. The identification of 20 inland barley types indicated multiple origins of Qingke in Tibet. The distribution of the five types of Qingke corresponded to specific environments. Two predominant highland-adaptative variations were identified for low temperature tolerance and grain color. Our results provide new insights into the origin, genome differentiation, population structure and highland adaptation in highland barley which will benefit both germplasm enhancement and breeding of naked barley.

CircSCAPER contributes to IL-1ß-induced osteoarthritis in vitro via miR-140-3p/EZH2 axis.

AIMS: Circular RNA (circRNA) S-phase cyclin A-associated protein in the endoplasmic reticulum (ER) (circSCAPER, ID: hsa_circ_0104595) has been found to be highly expressed in osteoarthritis (OA) patients and has been associated with the severity of OA. Hence, the role and mechanisms underlying circSCAPER in OA were investigated in this study. METHODS: In vitro cultured human normal chondrocyte C28/I2 was exposed to interleukin (IL)-1ß to mimic the microenvironment of OA. The expression of circSCAPER, microRNA (miR)-140-3p, and enhancer of zeste homolog 2 (EZH2) was detected using quantitative real-time polymerase chain reaction and Western blot assays. The extracellular matrix (ECM) degradation, proliferation, and apoptosis of chondrocytes were determined using Western blot, cell counting kit-8, and flow cytometry assays. Targeted relationships were predicted by bioinformatic analysis and verified using dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The levels of phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) pathway-related protein were detected using Western blot assays. RESULTS: CircSCAPER was highly expressed in OA cartilage tissues and IL-1ß-induced chondrocytes. Knockdown of circSCAPER reduced IL-1ß-evoked ECM degradation, proliferation arrest, and apoptosis enhancement in chondrocytes. Mechanistically, circSCAPER directly bound to miR-140-3p, and miR-140-3p inhibition reversed the effects of circSCAPER knockdown on IL-1ß-induced chondrocytes. miR-140-3p was verified to target EZH2, and overexpression of miR-140-3p protected chondrocytes against IL-1ß-induced dysfunction via targeting EZH2. Additionally, we confirmed that circSCAPER could regulate EZH2 through sponging miR-140-3p, and the circSCAPER/miR-140-3p/EZH2 axis could activate the PI3K/AKT pathway. CONCLUSION: CircSCAPER promoted IL-1ß-evoked ECM degradation, proliferation arrest, and apoptosis enhancement in chondrocytes via regulating miR-140-3p/EZH2 axis, which gained a new insight into the pathogenesis of OA. Cite this article: Bone Joint Res 2022;11(2):61-72.

Effects of Two Starch Synthase IIa Isoforms on Grain Components and Other Grain Traits in Barley.

Starch biosynthesis in cereal crops is a complex pathway regulated by multiple starch synthetic enzymes. Starch synthase IIa (SSIIa) is well-known to be one of the major starch synthases and is very important in amylopectin biosynthesis. It has significant effects on grain composition and kernel traits. However, there are few reports on the association of natural variation of SSIIa in barley and grain composition and characteristics. In this work, two SSIIa isoforms were first identified as SSIIaH and SSIIaL by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis, mass spectrometry, and Western blotting. Sequence analysis of the SSIIa gene demonstrated that a 33 bp insertion coding a peptide of APPSSVVPAKK caused different SSIIa, e.g., SSIIaH and SSIIaL. Based on this molecular difference, a polymerase chain reaction marker was developed, which could be used to screen different SSIIa genotypes easily. Kernel hardness of SSIIaL genotypes was significantly higher than that of SSIIaH Chinese barley cultivars. The proportion of SSIIaL genotypes was extremely low in Australian barley cultivars (5/24) and much higher in Tibetan hull-less barley cultivars (46/74), consistent with the end-use requirements of barley grain. This study provided new information in barley endosperm starch synthesis and indicated that it is valuable for choosing the preferred SSIIa genotype according to the end-use requirements.

Digit replantation in Tibetan plateau: 12 cases report / 中华显微外科杂志

Objective:To report the clinical outcome of finger replantation in Tibetan plateau.Methods:From August, 2018 to August, 2019, a total of 12 patients with 15 amputed digits treated in the Department of Emergency of Lasa People’s Hospital. All these cases were performed replantation without exclusion, including 4 cases of machine-mangled injury, 3 cases of steel rope crushing injury, 4 cases of electric saw injury, and 1 case of rotation avulsed injury. Replantations were performed under microscope by a fresh team of microsurgery surgeons. Antibiotics, anticoagulants and vasodilators were prescribed postoperatively. Application of oxygen inhalation through nasal tube and warm room temperature were advised. Tabaco and coffin were strictly forbidden postoperatively. All patients were regular followed-up after operation.Results:Twelve out of total 15 amputed digits successfully replanted, 3 digits turned to necrosis eventually. The survival rate was 80% (12/15). All cases were followed up for 4-16 months. According to the Functional Evaluation Standard of Replantation by the Hand Surgery Society of Chinese Medical Association, the results were excellent in 3 digits, good in 7 digits, fair in 1 digit, poor in 4 digits. The excellent and good rate was 66.6%(10/15).Conclusion:In this group, the survival rate and excellent and good rate of finger replantation in Tibetan plateau is unexpected high. Thus, it is deducible that digit amputation can be successfully replanted with good functional result when meticulous microsurgical techniques are applied, although the unique adverse factors of Tibetan plateau exist.

The draft genome of Tibetan hulless barley reveals adaptive patterns to the high stressful Tibetan Plateau.

The Tibetan hulless barley (Hordeum vulgare L. var. nudum), also called "Qingke" in Chinese and "Ne" in Tibetan, is the staple food for Tibetans and an important livestock feed in the Tibetan Plateau. The diploid nature and adaptation to diverse environments of the highland give it unique resources for genetic research and crop improvement. Here we produced a 3.89-Gb draft assembly of Tibetan hulless barley with 36,151 predicted protein-coding genes. Comparative analyses revealed the divergence times and synteny between barley and other representative Poaceae genomes. The expansion of the gene family related to stress responses was found in Tibetan hulless barley. Resequencing of 10 barley accessions uncovered high levels of genetic variation in Tibetan wild barley and genetic divergence between Tibetan and non-Tibetan barley genomes. Selective sweep analyses demonstrate adaptive correlations of genes under selection with extensive environmental variables. Our results not only construct a genomic framework for crop improvement but also provide evolutionary insights of highland adaptation of Tibetan hulless barley.