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Nonobstructive azoospermia (NOA) is considered to be the most severe form of male infertility. Meiotic arrest is one of the major causes of NOA and can be caused by single gene mutations. Here, a novel homozygous missense mutation (c.131G>T) in the MEI1 gene was identified through whole exome sequencing in a Chinese men with NOA caused by meiotic arrest. Bioinformatics and genetic analysis predicted that this novel mutation may be deleterious. Our findings confirm that spermatogenesis is arrested at the primary spermatocyte stage, with defective programed DNA double‐strand breaks (DSBs) formation. In vitro functional analysis revealed that the defects of DSBs formation may be a result of a lower expression level of MEI1 protein in the mutant. Therefore, the NOA in this patient is likely caused by the single novel mutation in the MEI1 gene leading to meiotic arrest. Our report expands the mutation spectrum of MEI1 and provides new evidence that the MEI1 gene may serve as a diagnostic marker for genetic counseling in NOA patients. [ABSTRACT FROM AUTHOR]

SUMMARY: Seed vigor has major impact on the rate and uniformity of seedling growth, crop yield, and quality. However, the epigenetic regulatory mechanism of crop seed vigor remains unclear. In this study, a (jumonji C) JmjC gene of the histone lysine demethylase OsJMJ718 was cloned in rice, and its roles in seed germination and its epigenetic regulation mechanism were investigated. OsJMJ718 was located in the nucleus and was engaged in H3K9 methylation. Histochemical GUS staining analysis revealed OsJMJ718 was highly expressed in seed embryos. Abiotic stress strongly induced the OsJMJ718 transcriptional accumulation level. Germination percentage and seedling vigor index of OsJMJ718 knockout lines (OsJMJ718‐CR) were lower than those of the wild type (WT). Chromatin immunoprecipitation followed by sequencing (ChIP‐seq) of seeds imbibed for 24 h showed an increase in H3K9me3 deposition of thousands of genes in OsJMJ718‐CR. ChIP‐seq results and transcriptome analysis showed that differentially expressed genes were enriched in ABA and ethylene signal transduction pathways. The content of ABA in OsJMJ718‐CR was higher than that in WT seeds. OsJMJ718 overexpression enhanced sensitivity to ABA during germination and early seedling growth. In the seed imbibition stage, ABA and ethylene content diminished and augmented, separately, suggesting that OsJMJ718 may adjust rice seed germination through the ABA and ethylene signal transduction pathways. This study displayed the important function of OsJMJ718 in adjusting rice seed germination and vigor, which will provide an essential reference for practical issues, such as improving rice vigor and promoting direct rice sowing production. Significance Statement: Understanding of the molecular mechanisms involved in seed vigor is an important objective in plant biology studies, and could be used to improve grain yields and seed quality. This study reported the important role of OsJMJ718 in regulating rice seed germination and vigor, which will provide an essential reference for practical issues, such as improving rice vigor and promoting direct rice sowing production. [ABSTRACT FROM AUTHOR]

Human parvovirus B19 (B19V) and human parvovirus 4 (PARV4) are known to infect humans and transmit through contaminated blood and blood products. Globally, three genotypes of B19V, as well as PARV4, have been identified, respectively. The existence of different B19V genotypes in Chinese plasma donors has been investigated, however, the data regarding PARV4 were not available. The main objective of this study is to identify the genotypes of PARV4 circulating in Chinese plasma donors. By using a duplex quantitative polymerase chain reaction assay adapted for all genotypes of B19V and PARV4, 78 source plasma pools for fractionation were screened and quantified. Results showed that positive rates of B19V and PARV4 DNA in plasma pool samples were 25.64% and 14.10%, respectively. PARV4 sequences in two positive samples were next genotyped, and these two sequences belonged to PARV4 genotypes 1 and 2, respectively. In conclusion, the data present demonstrate the existence of PARV4 genotypes 1 and 2 in Chinese plasma donors for the first time and also show the relatively lower prevalence and level of PARV4 DNA in Chinese plasma donors in comparison with that of B19V DNA. Highlights: At least two PARV4 genotypes, 1 and 2, were currently present in China.The prevalence and level of PARV4 DNA in Chinese plasma donors were relatively lower in comparison with that of B19V DNA.The rate of B19V and PARV4 coinfection in Chinese source plasma pools was low. [ABSTRACT FROM AUTHOR]

Adverse environmental stresses affect plant growth and crop yields. Sheepgrass (Leymus chinensis (Trin.) Tzvel), an important forage grass that is widely distributed in the east of Eurasia steppe, has high tolerance to extreme low temperature. Many genes that respond to cold stress were identified in sheepgrass by RNA‐sequencing, but more detailed studies are needed to dissect the function of those genes. Here, we found that LcFIN2, a sheepgrass freezing‐induced protein 2, encoded a chloroplast‐targeted protein. Expression of LcFIN2 was upregulated by freezing, chilling, NaCl and abscisic acid (ABA) treatments. Overexpression of LcFIN2 enhanced the survival rate of transgenic Arabidopsis after freezing stress. Importantly, heterologous expression of LcFIN2 in rice exhibited not only higher survival rate but also accumulated various soluble substances and reduced membrane damage in rice under chilling stress. Furthermore, the chlorophyll content, the quantum photochemistry efficiency of photosystem II (ΦPSII), the non‐photochemical quenching (NPQ), the net photosynthesis rate (Pn) and the expression of some chloroplast ribosomal‐related and photosynthesis‐related genes were higher in the transgenic rice under chilling stress. These findings suggested that the LcFIN2 gene could potentially be used to improve low‐temperature tolerance in crops. [ABSTRACT FROM AUTHOR]

Abstract: α1‐Antitrypsin (AAT) is widely used to treat patients with congenital AAT deficiency. Cohn Fraction IV (Cohn F IV) is normally discarded during the manufacturing process of albumin but contains approximately 33% of plasma AAT. We established a new process for large‐scale purification of AAT from it. liquid chromatography‐electrospray ionization‐tandem mass spectrometry and high‐performance liquid chromatography were applied for qualitative identification and composition analysis, respectively. Stabilizers were optimized for AAT activity protection during lyophilization and dry‐heat. Virus inactivation by dry‐heat and solvent/detergent (S/D) was validated on a range of viruses. AAT with purity of 95.54%, specific activity of 3,938.5 IU/mg, and yield of 26.79%, was achieved. More than 95% activity was reserved after S/D. More than 96% activity was obtained after lyophilization or dry‐heat. After S/D, pseudorabies virus (PRV) and vesicular stomatitis virus (VSV) were inactivated below detectable level within 1 H. Virus titer reductions of more than 5.50 log10 and 5.38 log10 were achieved for PRV and VSV, respectively. Porcine parvovirus and encephalomyocarditis virus were inactivated by 3.17 log10 and 5.88 log10 reduction after dry‐heat. The advantages of this process, including suitability for large‐scale production, high purity, better utilization of human plasma, viral safety, commercial and inexpensive chromatography medium, may facilitate its further application. [ABSTRACT FROM AUTHOR]

Background: α2-Macroglobulin (α2-M) has a curative effect on radiation injury. Virus transmission through plasma derivatives is still not risk-free. Effect of dry heat on α2-M activity and virus inactivation by dry heat in a new manufacturing process of α2-M were studied.Study Design and Methods: Effects of 100°C for 30 minutes, 80°C for 72 hours, and lyophilization on α2-M activity were detected, and stabilizing agents were optimized. Effect of a treatment at 100°C for 30 minutes has been tested on a range of viruses and characteristics change of α2-M was investigated.Results: More than 90 and 80% α2-M activity recovery were reserved after treatment at 100°C for 30 minutes and 80°C for 72 hours, respectively. A concentration of 0.05 mol/L histidine presented a better protecting effect for α-M activity. No substantial changes were observed in the characteristics of α2-M compared with the untreated. By lyophilization and dry-heat treatment at 100°C for 30 minutes, murine encephalomyocarditis virus and pseudorabies virus (PRV) were inactivated below detectable level within 5 minutes (virus titers reduction ≥ 5.75 log) and 30 minutes (virus titers reduction ≥ 6.00 log), respectively. Bovine viral diarrhea virus and porcine parvovirus were inactivated by 4.29 and 2.46 log reduction, respectively.Conclusion: Treatment at 100°C for 30 minutes could improve the virus safety of α2-M with a slight activity loss. [ABSTRACT FROM AUTHOR]

As a perennial forage crop broadly distributed in eastern Eurasia, sheepgrass ( Leymus chinensis ( Trin.) Tzvel) is highly tolerant to low-temperature stress. Previous report indicates that sheepgrass is able to endure as low as −47.5 °C,allowing it to survive through the cold winter season. However, due to the lack of sufficient studies, the underlying mechanism towards the extraordinary low-temperature tolerance is unclear. Although the transcription profiling has provided insight into the transcriptome response to cold stress, more detailed studies are required to dissect the molecular mechanism regarding the excellent abiotic stress tolerance. In this work, we report a novel transcript factor Lc FIN1 ( L. chinensis freezing-induced 1) from sheepgrass. Lc FIN1 showed no homology with other known genes and was rapidly and highly induced by cold stress, suggesting that Lc FIN1 participates in the early response to cold stress. Consistently, ectopic expression of Lc FIN1 significantly increased cold stress tolerance in the transgenic plants, as indicated by the higher survival rate, fresh weight and other stress-related indexes after a freezing treatment. Transcriptome analysis showed that numerous stress-related genes were differentially expressed in Lc FIN1-overexpressing plants, suggesting that Lc FIN1 may enhance plant abiotic stress tolerance by transcriptional regulation. Electrophoretic mobility shift assays and CHIP- qPCR showed that Lc CBF1 can bind to the CRT/ DRE cis-element located in the promoter region of Lc FIN1, suggesting that Lc FIN1 is directly regulated by Lc CBF1. Taken together, our results suggest that Lc FIN1 positively regulates plant adaptation response to cold stress and is a promising candidate gene to improve crop cold tolerance. [ABSTRACT FROM AUTHOR]