The interaction between ADAM22 and 14-3-3β

ADAM family consists of a number of transmembrane proteins that contain a disintegrin and metalloprotease domain. ADAMs are involved in a highly diverse set of biological processes, including fertilization, neurogenesis, myogenesis and inflammatory response. The ADAM proteins have both cell adhesion and protease activities.Adam22 is highly expressed in human brain. Theadam22-/- mice presented severe ataxia and died before weaning, but the function of ADAM22 is still unknown. 14-3-3 β interacting with ADAM22 was detected by using yeast two-hybrid assay. The specificity of interaction between ADAM22 and 14-3-3β was proved byin vitro binding assay and immunoprecipitation. The major 14-3-3β binding site was located in the last 28 amino acid residues of ADAM22 cytoplasmic tail. Protein 14-3-3β is abundant and plays an important role in mediating cell diffusion, migration and cell cycle control. The interaction of ADAM22 and 14-3-3β suggests that the ADAM22 may play a crucial role in neural function and development.     

干旱胁迫对沙冬青叶片防御光破坏机制的影响

沙冬青(Ammopiptanthus mongolicus (Maxim.) Cheng f.)是生长在沙漠及干旱荒漠地区的常绿灌木.在夏季,其叶片经常遭受中午强光(超过1 500 μmol*m-2*s-1) 胁迫,出现明显的光抑制现象.我们利用便携式光合测定系统(CIRAS-1)和脉冲调制荧光仪(MFMS-2)测定了自然形成的干旱胁迫条件下沙冬青光合和荧光参数的日变化,主要探讨了干旱胁迫对沙冬青叶片防御强光破坏机制的影响.结果表明,正常水分和干旱胁迫下,沙冬青叶片的净光合速率(Pn)、 PSⅡ最大光化学效率(Fv/Fm)和PSⅡ非环式电子传递效率(ΦPSⅡ)在中午都明显降低;相对正常水分条件而言,干旱胁迫下初始荧光(Fo)先下降后上升,荧光的非光化学淬灭(NPQ)上升较快并在一定水平上维持不变.由此推断晴天中午沙冬青叶片在正常水分条件下主要采取依赖叶黄素循环的热耗散机制;而在干旱胁迫条件下主要采取了依赖叶黄素循环的热耗散和PSⅡ反应中心可逆失活两种保护机制.     

育秧箱全量施肥对水稻产量和氮素流失的影响

采用育秧箱全量施肥技术,通过2年田间小区试验,研究中量控释氮肥(80 kg N·hm-2)、高量控释氮肥(120kgN·hm-2)和常规施肥(300 kg N·hm-2)处理对水稻产量和氮素流失的影响.结果表明:与常规施肥相比,高量控释氮肥处理的水稻产量未显著降低.常规施肥处理2年平均氮素利用率为33.2％,中量和高量控释氮肥处理的平均氮素利用率分别比常规施肥处理提高26.2％和20.7％.常规施肥处理田面水的总氮含量在施肥后1～3d达最大值,中量和高量控释氮肥处理的高峰期为施肥后7～9d,全生育期内,中量和高量控释氮肥处理田面水的总氮含量均显著低于常规施肥处理.常规施肥处理的氮素渗漏流失主要在分蘖期,中量和高量控释氮肥处理的氮素渗漏流失后移至分蘖-开花期.各处理硝态氮流失量占总氮流失量的59.7％～64.2％,高量控释氮肥处理的总氮净流失量比常规施肥处理减少51.8％.     

嗜酸乳杆菌在模拟胃肠环境中抗性的研究

采用MRS培养基,模拟胃肠环境,即低pH值（1.5～4.5）。高胆汁盐（0.1％～0.4％）对嗜酸乳杆菌抗性进行了研究。同时对肠道中致病性大肠杆菌、金黄色葡萄球菌的拮抗特性以及服用抗生素后嗜酸乳杆菌的耐药性进行了研究。结果表明,嗜酸乳杆菌在pH2.5～4.5时具有较强的生存能力,6h活菌数仍达 10⁷cfu/mL以上,pH1.5条件下仍有部分存活。在0.1％～0.3％胆汁盐条件下4h活菌数仍达106cfu/mL以上,且能在0.4％胆汁盐中存活。同时,对致病性大肠杆菌和金黄色葡萄球菌具     

几种灌木、半灌木对沙地土壤肥力影响机制的研究

研究了科尔沁地广泛分布的几种灌木和半灌木的“肥岛”和根际效应。结果表明,在灌丛下土壤有机C、全N和全P分别比灌丛间地高56％、51％和37％,土壤电导率（EC）提高了56％,但pH值并无明显变化;灌木根际土壤较非根际土壤有机C和全N分别高76％和54％,根际土壤pH降低0．19个单位,EC提高了2－3倍,但土壤全P并无显著变化,灌丛下土壤发和根际中土壤养分含量显著相关,表明丛肥岛的利于根系的生长,导致更多的根际沉积;而根系的活动又促进了肥岛的发育,灌丛对沙地土壤肥力的影响机制在于：灌丛对土壤风蚀物质、降尘和凋落物等的截获,形成灌丛“肥岛”;并通过发达的根系以根际沉积的形式向土壤输入大量的有机物质,从而使周围土壤的肥力性关得以改善。     

Preliminarily functional analysis of a cloned novel human

ADAM is a family of type I integral membrane proteins which are characterized by sharing a disintegrin and metalloprotease domain and involved in many important physiological processes such as fertilization, neurogenesis and inflammatory response. A novel human ADAM gene--ADAM29, which was cloned in our laboratory, is exclusively expressed in human testis andcontains a potential fusion domain. A full-length cDNA of ADAM29 was obtained by using multiple-step PCR. Phylogenetic tree of known mammalian ADAMs specifically expressed in testis was reconstructed. Polyclonal antiserum was raised by immunizing the rabbits with sub-peptide of ADAM29 (Leu268-Asp374) as immunogen. The result of immunohistochemical test on human testis showed that ADAM29 is expressed in different stages of spermatogenesis and in interstitial cells. ADAM29 may play a certain role in the signal transduction during the maturation of tes-tis-associated cells.     

福建省山苍籽果实的精油成份分析

本文报道了使用蒸馏、干柱层析、薄层层析、毛细管气相色谱、色谱-质谱联机等手段,分析了福建省几个产地的山苍籽商品精油成份,鉴定出26种成份,其中α-正丁酮、β-水芹烯、β-蒎烯、顺式-芳樟醇氧化物、反式-芳樟醇氧化物、正十一烷、α-龙脑烯、龙脑、萜品-4醇、正十二烷、胡椒酮、三甲基十二烷等12种成份,均未见报道过;对鉴定成份进行定量分析。     

小鼠BW5147细胞与网织红细胞融合后cAMP水平及其磷酸二酯酶的细胞化学观察

本实验用PEG介导,将小鼠BW_(5147)细胞与小鼠网织红细胞在体外进行悬浮融合,经HAT选择性培养基筛选获得的胞质杂交细胞,表现出增殖减慢、生长率下降、生瘤能力降低等去恶化现象。本实验从cAMP-PDE细胞化学反应显示出胞质杂交细胞内cAMP-PDE活性比亲本BW_(5147)瘤细胞有所减弱,而cAMP水平则有所升高,提示胞质杂交细胞恶性程度下降可能与细胞内cAMP-PDE活性降低和cAMP水平升高具有一定的关系。本实验的结果将为进一步探索促使肿瘤细胞逆转的可能途径提供一定的依据。