葡萄试管苗热处理结合茎尖培养脱病毒效果的研究

对７个生食葡萄品种的试管苗热处理结合茎尖剥离培养脱除病毒的方法做了研究,结果表明,从热处理试管苗剥离的茎尖培养成活率为６１．２％,其中有１８．１％的成苗。各品种热处理试管苗剥离的茎尖分化再生能力不同：先形成愈伤组织的成苗率较低,而先分化芽的茎尖成苗率较高。这一方法对扇叶病毒和卷叶病毒的脱除率达９２％以上。     

组织器官通讯对骨骼肌发育的作用及调控机制研究进展

骨骼肌是动物机体最重要的器官之一,研究骨骼肌发育调控机制对于肌肉相关疾病的诊断以及家畜肉质的改善都有着重要意义。骨骼肌发育调控是一个复杂的过程,受到大量肌肉分泌因子和信号通路的调节。此外,为了维持体内代谢稳态并最大限度地利用能量,机体协调多个组织器官形成了复杂而又精密的代谢调控网络,对于调控骨骼肌发育也发挥着重要的作用。随着组学技术的发展,人们对于组织器官通讯的潜在机制进行了深入研究。本文综述了脂肪组织、神经组织、肠道等组织器官通讯对于骨骼肌发育的影响,以期为靶向调控骨骼肌发育提供理论基础。     

Dracorhodin perchlorate inhibits osteoclastogenesis through repressing RANKL-stimulated NFATc1 activity

Osteolytic skeletal disorders are caused by an imbalance in the osteoclast and osteoblast function. Suppressing the differentiation and resorptive function of osteoclast is a key strategy for treating osteolytic diseases. Dracorhodin perchlorate (D.P), an active component from dragon blood resin, has been used for facilitating wound healing and anti-cancer treatments. In this study, we determined the effect of D.P on osteoclast differentiation and function. We have found that D.P inhibited RANKL-induced osteoclast formation and resorbed pits of hydroxyapatite-coated plate in a dose-dependent manner. D.P also disrupted the formation of intact actin-rich podosome structures in mature osteoclasts and inhibited osteoclast-specific gene and protein expressions. Further, D.P was able to suppress RANKL-activated JNK, NF-κB and Ca²⁺ signalling pathways and reduces the expression level of NFATc1 as well as the nucleus translocation of NFATc1. Overall, these results indicated a potential therapeutic effect of D.P on osteoclast-related conditions.     

Liver X receptor activation induces podocyte injury via inhibiting autophagic activity

Podocyte injury plays a key role in the occurrence and development of kidney diseases. Decreased autophagic activity in podocyte is closely related to its injury and the occurrence of proteinuria. Liver X receptors (LXRs), as metabolic nuclear receptors, participate in multiple pathophysiological processes and express in several tissues, including podocytes. Although the functional roles of LXRs in the liver, adipose tissue and intestine are well established; however, the effect of LXRs on podocytes function remains unclear. In this study, we used mouse podocytes cell line to investigate the effects of LXR activation on podocytes autophagy level and related signaling pathway by performing Western blotting, RT-PCR, GFP-mRFP-LC3 transfection, and immunofluorescence staining. Then, we tested this effect in STZ-induced diabetic mice. Transmission electron microscopy and immunohistochemistry were employed to explore the effects of LXR activation on podocytes function and autophagic activity. We found that LXR activation could inhibit autophagic flux through blocking the formation of autophagosome in podocytes in vitro which was possibly achieved by affecting AMPK, mTOR, and SIRT1 signaling pathways. Furthermore, LXR activation in vivo induced autophagy suppression in glomeruli, leading to aggravated podocyte injury. In summary, our findings indicated that activation of LXRs induced autophagy suppression, which in turn contributed to the podocyte injury.

     

Dynamic changes of histone H3 lysine 9 following trimethylation in bovine oocytes and pre-implantation embryos

Objectives

We have examined dynamic changes of histone H3 lysine 9 following trimethylation (H3K9me3), the mRNA expression levels of SUV39H1 and SUV39H2 in bovine oocytes and the role in the development of in vitro fertilization (IVF) pre-implantation embryos.

Results

There were strong H3K9me3 signals in germinal vesicle (GV) oocytes but no signals in MII oocytes. H3K9me3 signals were maintained during IVF pre-implantation embryo development. SUV39H1 and SUV39H2 showed significantly higher mRNA expression levels in GV oocytes than MII oocytes (P < 0.01). SUV39H1 showed high mRNA expression level in two-cell embryos, however, SUV39H2 showed high mRNA expression level in four-cell embryos. In other development stage, SUV39H1 and SUV39H2 showed low expression levels.

Conclusion

Bovine IVF pre-implantation embryos maintain strong H3K9me3 signals and SUV39H1 and SUV39H2 are highly expressed at the early development stage of pre-implantation embryos.

     

锌胁迫对彩色豆马勃体内锌的分布和活性形态及其抗氧化系统的影响

彩色豆马勃Pisolithus tinctorius可广泛与林木建立外生菌根,其共生可促进植物生长,提高植物对重金属的耐受性。然而,关于彩色豆马勃对重金属锌(Zn)胁迫的生理响应还不完全清楚。本研究在纯培养条件下,测定了Zn胁迫对彩色豆马勃生物量、Zn的活性形态和亚细胞分布,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性,谷胱甘肽(GSH)、抗坏血酸(AsA)和黑色素含量的影响。结果表明,Zn胁迫抑制了彩色豆马勃的生长,在浓度为563 μmol/L时,达到半数最大抑制浓度(IC₅₀),在浓度为600 μmol/L时,生物量降低42.6%。Zn在彩色豆马勃中以活性较低的草酸盐、难溶于水的磷酸盐、果胶酸盐以及与蛋白质呈结合态或吸着态的形式为主。Zn胁迫显著提高了彩色豆马勃菌丝中CAT、POD和SOD活性,增加了GSH和黑色素含量,但对AsA的含量没有显著影响。本研究表明,彩色豆马勃主要通过调节Zn的分布及抗氧化系统,增加黑色素含量,增强对Zn的耐受性,为外生菌根真菌修复重金属污染土壤提供了理论支持。