两种灯笼果生物学特性观察

通过对外地种和本地种两种灯笼果相关性状的观测,发现将东北的灯笼果引种到海南能够正常生长,并从多方面详细描述了本地种和外地种灯笼果在海南栽培的性状表现。     

脱落酸对香蕉幼苗抗寒性的影响

分别用不同浓度的脱落酸(ABA)溶液喷洒香蕉幼苗后,模拟自然降温过程进行冷胁迫处理,发现不同浓度的ABA均不同程度地提高香蕉幼苗冷胁迫期间叶片SOD活性及MDA、可溶性糖和可溶性蛋白含量,降低细胞质泄漏,减缓叶绿素降解,减少叶片萎蔫面积和死亡率,从而缓解了低温对香蕉幼苗的冷伤害程度,其中以浓度为20mg/L的ABA保护效应最明显。     

高原家养动物环境适应性的研究进展

青藏高原环境主要体现为低氧低压、寒冷干燥、紫外线强、食物匮乏等，而高原家养动物经历了长期的选择和培育后能够生活在此环境下，其机体已经形成了独特的高原适应性特征。由于高原畜禽机体适应进化体系的复杂性，全面系统的适应性分子机制解析尚未完善。随着分子生物学和生物信息学的发展，高原家养动物基因组组装和功能注释完成，然后逐步开展了基因组、转录组和蛋白质组等组学层面的工作，挖掘到一系列高原动物环境适应性关键候选基因，为解析高原家养动物环境适应性分子机制研究提供了强有力支撑。本文以世居在青藏高原的藏鸡（Gallus gallus）、藏猪（Sus scrofa）、牦牛（Bos grunniens）、藏山羊（Capra hircus）、藏绵羊（Ovis aries）、藏马（Equus caballus）和藏獒（Canis lupus familiaris）等高原土著畜禽资源作为分类单元，分别从组织器官的解剖学结构、血液生理生化指标和分子遗传机制解析3个方面进行论述，并对高原适应性进化的研究趋势进行展望，以期为下一步培育高原高寒低氧地区新品种奠定基础。     

Successful Production of Offspring Using Cryopreserved Sperm via Nonsurgical Artificial Insemination in Rats

In rats, artificial insemination (AI) is surgically performed as a general tool to obtain offspring using cryopreserved spermatozoa. Nonsurgical AI is a more desirable technology because it does not require any surgical procedures. However, there has never been a successful nonsurgical AI since frozen-thawed rat spermatozoa show low motility. We show here for the first time successful nonsurgical AI in rats using oxytocin treatment. Intraperitoneal injection of oxytocin (1/800 IU) immediately before nonsurgical AI significantly increased the number of sperm collected from the oviducts compared with that without oxytocin treatment. Therefore, to obtain pups, oxytocin was intraperitoneally injected into females mated with vasectomized males, and the rats were then used for nonsurgical AI. Seven of the 12 oxytocin-treated rats became pregnant after nonsurgical AI, and 37 pups were obtained. Only one rat (1/13) without oxytocin treatment was pregnant after nonsurgical AI, and only 1 pup was delivered. These results show success for the first time in obtaining offspring using frozen-thawed rat spermatozoa via nonsurgical AI. Our results also suggest the possibility that oxytocin treatment is effective for improvement of nonsurgical AI even in other species.     

活性炭与大孔树脂对美洲大蠊脱脂膏的脱色效果比较(英文)

[目的]探讨活性炭及大孔树脂两种脱色工艺对美洲大蠊脱脂膏的脱色效果,对比两种脱色工艺的优缺点。[方法]美洲大蠊脱脂膏用活性炭和大孔树脂脱色后,进行冷冻干燥得到固体脱色物,然后通过考察收得率、脱色率、蛋白保留率及脱色的操作过程,比较两种脱色工艺的有缺点。[结果]两种方法均能用于脱色。从收得率及蛋白保留率看,大孔树脂优于活性炭;从脱色率及操作过程看,活性炭脱色优于大孔树脂。[结论]该研究结果表明,若试验所需成分以蛋白为主,可采用大孔树脂脱色;若所需成分不是以蛋白为主,则可采用活性炭脱色。     

杧果MADS-box基因保守区片段的克隆与序列分析

为从杧果中克隆新的MADS-box基因,利用MADS-box转录因子的保守特征设计简并引物,应用RT-PCR从杧果花序中成功分离出14条MADS-box基因cDNA片段。片段长度在138~147bp之间,推导的氨基酸序列与已知的杧果MADS-box基因的同源性为65.2%~82.6%。用推导的氨基酸序列与已知的杧果和拟南芥MADS-box基因进行系统发育分析,可将这些片段归入MADS-box的不同亚家族中。表明杧果花序中存在多种MADS-box转录因子,参与杧果花器官的发育及开花时间的调节。     

Phospholipase Cζ (PLCζ) versus postacrosomal sheath WW domain‐binding protein (PAWP): Which molecule will survive as a sperm factor?

During mammalian fertilization, sperm is fused with the oocyte's membrane, triggering the resumption of meiosis from the metaphase II arrest, the extrusion of the second polar body, and the exocytosis of cortical granules; these events are collectively called 'oocyte activation.' In all species studied to date, the transient rise in the cytosolic level of calcium (in particular, the repeated calcium increases called 'calcium oscillations' in mammals) is required for these events. Researchers have focused on identifying the factor(s) that can induce calcium oscillations during fertilization. Sperm‐specific phospholipase C, i.e., PLC zeta (PLCζ), is a strong candidate of the factor(s), and several research groups using different species obtained evidence that PLCζ is a sperm factor that can induce calcium oscillations during fertilization. However, postacrosomal sheath Tryptophan‐Tryptophan (WW)—domain‐binding protein (PAWP) was recently shown to have a pivotal role in inducing calcium oscillations in some species. In this review, we focus on PLCζ and PAWP as sperm factors, and we discuss this controversy: Which of these two molecules survives as a sperm factor?     

The effect of M‐phase stage‐dependent kinase inhibitors on inositol 1,4,5‐trisphosphate receptor 1 (IP3R1) expression and localization in pig oocytes

At fertilization, inositol 1,4,5‐trisphosphate receptor type 1 (IP₃R1) has a crucial role in Ca²⁺ release in mammals. Expression levels, localization and phosphorylation of IP₃R1 are important for its function, but it still remains unclear which molecule(s) regulates IP₃R1 behavior in pig oocytes. We examined whether there was a difference in localization of IP₃R1 after in vitro or in vivo maturation of pig oocytes. In mouse oocytes, large clusters of IP₃R1 were formed in the cortex of the oocyte except in a ring‐shaped band of cortex adjacent to the spindle. However, no such clusters of IP₃R1 were observed in pig oocytes and there was no difference in its localization between in vitro and in vivo matured oocytes. We next tried to clarify which factor(s) regulates IP₃R1 localization, phosphorylation and expression using M‐phase stage‐dependent kinase inhibitors. Our results show that treatments with roscovitine (p34^cdc2 kinase inhibitor) or U0126 (mitogen‐activated protein kinase inhibitor) did not affect IP₃R1 expression or localization in pig oocytes, although the latter strongly inhibited phosphorylation. However, treatment with BI‐2536, an inhibitor of polo‐like kinase 1 (Plk1), dramatically decreased the expression level of IP₃R1 in pig oocytes in a dose‐dependent manner. From these results, it is suggested that Plk1 is involved in the regulation of IP₃R1 expression in pig oocytes.     

国内外肉牛遗传评估体系概况

种公牛的选育是肉牛育种工作的核心。传统选育肉用种公牛需要经过后裔测定进行选择,其优点是准确性高,但存在周期长、屠宰和肉质性状难以收集、成本高等问题,致其选择效率低。自2001年全基因组选择概念提出后,该技术迅速成为动植物育种领域研究的热点。利用全基因组选择进行肉用种公牛的选育,进行早期选择从而大幅度缩短世代间隔,可以提高繁殖性状等低遗传力性状的选择准确性,加快遗传进展,并大大降低育种成本。2014年,美国安格斯协会开始应用全基因组选择技术,其他欧美发达国家也陆续使用,肉牛育种进入基因组时代。中国自2017年开始使用全基因组选择技术选择青年肉用种公牛,并于2020年在全国范围内使用该技术进行基因组遗传评估。本文综述了国内外肉牛遗传评估现状,以期为我国肉牛育种工作提供参考和借鉴。     

Three-dimensional structure of Hayabusa samples: origin and evolution of Itokawa regolith

Regolith particles on the asteroid Itokawa were recovered by the Hayabusa mission. Their three-dimensional (3D) structure and other properties, revealed by x-ray microtomography, provide information on regolith formation. Modal abundances of minerals, bulk density (3.4 grams per cubic centimeter), and the 3D textures indicate that the particles represent a mixture of equilibrated and less-equilibrated LL chondrite materials. Evidence for melting was not seen on any of the particles. Some particles have rounded edges. Overall, the particles' size and shape are different from those seen in particles from the lunar regolith. These features suggest that meteoroid impacts on the asteroid surface primarily form much of the regolith particle, and that seismic-induced grain motion in the smooth terrain abrades them over time.