Phytochrome controlled, long-day photoperiod-inducible protein in rice leaves

A new protein in the leaves of NK58S and NK58 (Oryza sativa L. subsp.japonica), which can be induced by 10 d-long-day photoperiod (14 h lightid) and cannot be induced by 10 d-short-day photoperiod (10 h light/d), has been found by two-dimensional gel electrophoresis. The protein, whose molecular weight and isoelectric point are 36 ku and pH 5.2 respectively, is found to be controlled by phytochrome as shown by the experiment of red light induction-far red light reversion.The existence of this protein in both NK58S and NK58 reflects that some of the responses of NK58S and NK58 might be similar in response to long-day photoperiod, a mild stress.     

水稻光敏核不育突变体与其原种的比较研究

本文对水稻光敏核不育突变体农垦５８Ｓ与其原种农垦５８进行了比较研究。结果表明，光敏核不育突变体农垦５８Ｓ与其原种农垦５８在各个生育期都存在明显的差异。农垦５８Ｓ表现出苗期株高、根长、叶绿素含量比农垦５８显著提高；生殖生长期，农垦５８Ｓ对光周期反应敏感，冠层叶片长度、株高、茎杆重和结实率在长日照或短日照处理下存在显著差异，农垦５８在生殖生长期对光周期反应不敏感。根据以上实验结果和已有的文献报道得出结论：水稻光敏核不育突变体农垦５８Ｓ不仅仅是雄性育性受育性转换期光周期调控这一个性状的突变，而且是同时伴随着多种性状的突变。     

光敏核不育水稻在不同光质下的叶绿素合成

光敏核不育水稻（农垦５８Ｓ）是从晚粳水稻农垦５８中发现的雄性不育自然突变体［１］,在两系杂交稻制种、增产上有巨大潜力．但是,光敏核不育的机理并不清楚,同时还存在温敏等问题．这些问题的解决有赖于加强基础研究,而对农垦５８Ｓ光生理学的研究是一个重要方面．...     

光敏核不育水稻中光敏色素Ⅰ的低温荧光分析

光敏核不育水稻中光敏色素Ⅰ的低温荧光分析王伟童哲（厦门大学生物学系厦门３６１００５）（中国科学院植物研究所北京１０００４４）光敏核不育水稻（农垦５８Ｓ）是从晚粳水稻农垦５８中发现的雄性不育自然突变体，是我国特有的水稻种质资源．农垦５８Ｓ的雄性不育由光...     

Biochemical characterization of the protein encoded by rice osRACD gene

A recombinant plasmid pET-racd was first constructed by cloning osRACD,the development-regulating gene that controls photoperiod fertility transformation in the photoperiod sensitive genic male sterile rice Nongken 58S,into a prokaryote expression vector pET28a(+).It was then transformed into E.Coli BL-21.Cutting with thrombin of the fusion protein extracted from transformants and PAGE separation yielded pure osRACD protein,which was further concentrated using ultrafiltration and renatured using glutathione oxidation/reduction refolding system for later functional study.As demonstrated by in vitro functional assay,the osRACD protein expressed in E.Coli B-21 shows remarkable activity in binding GTP specifically and hydrolyzing it.     

人工光周期及致盲对树鼩繁殖的影响

通过人工光周期及摘除眼球致盲，探讨了光照对昆明地区野生树（Ｔｕｐａｉａｂｅｌａｎｇｅｒｉｃｈｉｎｅｎｓｉｓ）繁殖的调控作用．非繁殖期人工长光照（１４．６Ｌ（光）：９．４Ｄ（暗））和人工长光照（１４．６Ｌ：９．４Ｄ）并致盲，都使树生殖器官重量和血浆睾酮、雌二醇含量以及除卵母细胞直径外的所有生殖器官形态学测量值极显著增加（Ｐ＜０．０１）；繁殖期人工短光照（１１．４Ｌ：１２．６Ｄ）可使生殖器官重量明显降低（Ｐ＜０．０１或０．０１＜Ｐ＜０．０５），使睾酮和雌二醇含量以及除卵了孢腔直径外的所有生殖器官形态学测量值极显著降低（Ｐ＜０．０１）；繁殖期人工短光照（１１．４Ｌ：１２．６Ｄ）并致盲可使所有指标都降低，但变化不显著（Ｐ＞０．０５）．结果表明，环境光周期是昆明地区树季节性繁殖的信号因子，在饲养条件下，可通过人工长光照提高树年繁殖率。     

松针褐斑病菌毒素活性的生物检测

松针褐斑病菌毒素不仅能伤害湿地松、火炬松等寄主植物的幼苗、针叶、根及愈伤组织，对非寄主植物水花生、紫茎泽兰的叶片也有伤害作用。在试验的几种生测材料中，湿地松愈伤组织对毒素伤害最敏感，湿地松幼苗、幼针叶，火炬松幼针叶和紫茎泽兰叶片次之，湿地松幼根、老针叶，火炬松老针叶，水花生和小麦叶片最不敏感。根据生测材料的敏感程度及表现症状的特异性分析可知，用湿地松、火炬松幼苗和幼针叶作生测材料较好，比较针刺法、浸渍法和涂抹法等几种生测方法表明，用针刺法接种毒素效果最好，其反应速度快，用量少，症状明显。因此建议在松针褐斑病菌毒素的生物检测中，以湿地松或火炬松幼苗或幼针叶作为材料，采用针刺法。     

拟南芥开花时间的分子遗传调控

拟南芥开花主要受四种遗传途径调控,即:光周期途径,春化途径,自主途径和赤霉素途径。各种途径之间通过CO,FLC,FT,SOC1等主效基因的相互作用,最终调节花特异性基因AP1和LFY的表达,从而调控拟南芥的开花时间,其中各种突变体的研究揭示了相关基因的功能。这些主效基因中,CO基因对光周期途径是特异的,FLC基因对开花起抑制作用。其它因素如环境、基因染色质结构的改变、酶等对拟南芥开花时间的影响有待进一步的研究。     

高温敏核不育水稻幼苗生长发育的热激反应

高温敏感核不育水稻培矮 64S 在热激处理后, 幼苗叶蛋白质组分与其可育条件下( 22℃ )相比, 表现出明显差异:在分子量为 97. 4~ 14. 4 KD 范围内共表现出 6 条蛋白质区带的变化, 其中 4 条新增加, 2 条减弱. 在热激条件下, 与常规稻湘晚籼 2号相比较, 培矮 64S 亦表现出了 7条蛋白质区带的变化.这些蛋白质组分的改变必然引起体内某些酶系统的变化,而影响幼苗的正常生长发育, 使幼苗生长受到明显抑制.     

植物生长调节剂促进红松提早结实技术研究

树木在幼年期是不能开花结实的,只有结束了幼年期达到性成熟阶段(即成年阶段)才能开花结实.在全面了解影响红松结实的遗传、起源、外界环境等主要因素的基础上,利用激素或激素类除草剂创造人工小环境,诱导促进红松造林苗提早结实取得了较好的试验效果.试验表明:结合优良造林苗木选择和配套造林技术,在红松新造林苗木成活后,于每年5月、7月上旬全株喷施特定浓度的赤霉素、ABT生根粉、乙烯利等植物激素能够促使红松实生苗提早结实,在实际操作中具有现实的有效性、操作性和实用性;红松S2-2优良苗木造林成活后,用2×10-4赤霉素全株喷雾处理,可使红松在第4年进入初果期.     

Fertility analysis of the Arabidopsis transformed with antisense rice osRACD gene

The full length osRACD cDNA sequence was subcloned into the pBI121 plasmid in the antisense orientation under the control of the CaMV35S promoter to construct the expression vector pBID, and the constructs were introduced into Arabidopsis plants by using the vacuum infiltration method. The siliques of the transformants stopped growing after anthesis, and they turned yellow or died later; and the siliques from the control plants transformed by the pBI continued growing after anthesis and matured normally. In vitro pollen germination demonstrated that the growth and elongation process of the pollens of the transgenic plants was inhibited, the pollen tubes were shorter and slightly fatter than the tubes of the control plants, which grew normally with long cyclindrical tubes. The above results suggest the function of osRACD gene involved in regulation of the growth and elongation process of pollen tube, its encoding protein may be one of the important factors in regulation of fertility transition of the photoperiod-sensitive genic male-sterile rice Nongken 58S.     

光周期条件对罗氏沼虾幼体存活率及体长生长率的影响

用４Ｌ：２０Ｄ、８Ｌ；１６Ｄ；１２Ｌ；１２Ｄ和２４Ｌ：０Ｄ四种光周期条件培养罗氏沼虾骚状幼体，观察其存活率和生长、发育情况。研究结果表明，随着光照时间的延长，特别是在连续照明的条件下，与最短的光照条件相比，幼体的存活率及体长生长率分别提高１５７．７％和２．２％ｄ，而育成Ｐ１的时间却相应缩短了１０ｄ。     

Isolation ofosRACD gene encoding a small GTP-binding protein from rice

Using an improved version of mRNA differential display technology, we have obtained a differentially displayed fragment RDP-8. Homologous comparison indicated that the fragment RDP-8 has high homology with the gene encoding maize small GTP-binding protein. By screening cDNA library of the rice Nongken 58N pan icle using the newly obtained fragment RDP-8 as probe, we further found the full-length cDNA of osRACD gene that encodes a rice small GTP-binding protein. Asco mpared with maize RACD gene, the osRACD of rice shows remarkable homology in both nucleotide sequence and amino acid sequence, 88% and 97% respectively. Evidence from RT-PCR study indicates that osRACD gene is related to photoperiod fertility conversion of photoperiod sensitive genic male sterility (PSGMS) rice.     

硫化氢供体硫氢化钠处理提高小麦对高温和干旱胁迫的综合抵抗能力

在动物体中,硫化氢（H2S）已被确认是继一氧化碳（CO）和一氧化氮（NO）后的第三种内源气体信号分子,它参与多种生理和病理过程。近年来,硫化氢的信号分子功能在植物体中也逐渐被揭示。本研究发现,用硫化氢供体硫氢化钠（NariS）处理小麦种子,可提高其在高温和干旱胁迫下的发芽率。此外,用NariS灌根处理小麦幼苗,可提高其在正常培养条件下的内源脯氨酸和可溶性糖含量,缓解二者在高温和干旱胁迫下的含量下降,减缓膜脂过氧化产物丙二醛（MDA）的积累,最终提高小麦幼苗在高温和干旱胁迫下的存活率,同时改善高温和干旱胁迫下的幼苗生长状况。这些结果表明硫化氢处理可提高小麦对高温和干旱胁迫的综合抵抗能力,并且这种综合抵抗能力的获得可能与硫化氢诱导脯氨酸和可溶性糖的积累有关。     

水稻黄绿叶基因YGLOSH的定位克隆

本文利用~(60)Co γ射线诱变光温敏感型核不育系广占63S(GZ63S),在后代中获得一个稳定遗传的黄绿化叶色突变体黄广占63S,突变体从苗期至成熟期均显示叶片黄化特征.遗传分析表明该性状受一对隐性核基因控制,命名为yglosh.利用BSA方法分析突变体黄广占63S与正常绿叶对照蜀恢881构建的F2群体,将该黄化基因定位于水稻2号染色体分子标记RM279和Pm6之间,物理距离约68kb.定位区间的cDNA测序分析发现,突变体中LOC_Os02g05890基因发生单碱基突变,形成终止子提前终止该基因的翻译.转基因互补实验确定LOC_Os02g05890为目标基因,可能参与叶绿体发育或者叶绿素生物合成途径.     

干旱对银杏生理生化特性及叶绿体超微结构的影响

以五年生盆栽的银杏大佛指实生苗为实验材料,通过持续自然干旱,研究了持续干旱条件下银杏叶片生理生化指标和叶绿体超微结构的变化.结果表明:干旱处理30 d后,银杏叶片叶绿素含量逐渐下降;MDA含量和SOD活力逐渐上升,CAT活力逐渐下降;脯氨酸和可溶性糖含量逐渐上升,可溶性蛋白质呈先下降后上升的趋势;各项生理指标(除SOD...     

Regulation of the G1-S transition in postembryonic neuronal precursors by axon ingrowth.

In the newly cellularized Drosophila embryo, progress through the cell cycle is regulated at the G2-M transition. We have examined cell-cycle regulation later in Drosophila development, in a group of postembryonic neuronal precursors. The S-phase precursor cells, which generate photoreceptor target neurons (lamina neurons) in the central nervous system, are not present in the absence of photoreceptor innervation. Here we report that axons selectively approach G1-phase precursors. Without axon ingrowth, lamina precursors do not enter their final S phase and by several criteria, arrest in the preceding G1 phase. These findings provide evidence that at this stage in development the control of cell division can occur at the G1-S transition.     

Role of src gene in growth regulation of Rous sarcoma virus-infected chicken embryo fibroblasts

We report here a study of the mechanisms leading to loss of growth control in chicken embryo fibroblasts transformed by Rous sarcoma virus (RSV). We have been particularly concerned with the role of the src gene in this process, and have used RSV mutants temperature sensitive (ts) for transformation to investigate the nature of the growth regulatory lesion. The two principal findings were (1) the stationary phase of the cell cycle (G1) in chick embryo fibroblasts seems to have two distinct regulatory compartments (using the terminology of Brooks et al. we refer to these as 'Q' and 'A' states). When rendered stationary at 41.5 degrees C by serum deprivation, normal cells enter a Q state, but cells infected with the ts-mutant occupy an A state. (2) Whereas normal cells can occupy either state depending on culture conditions, the ts-infected cells, at 41.5 degrees C, do not seem to enter Q even though a known src gene product, a kinase, is reported to be inactive at this temperature. We discuss the possibility that viral factors other than the active src protein kinase influence growth control in infected cultures.