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991.
类受体蛋白激酶(receptor-like protein kinase,RLK)是植物信号转导网络中的重要成员,参与介导生长、发育以及逆境胁迫应答等多种细胞代谢过程.在植物细胞中已发现和克隆了富含亮氨酸重复区型(LRR)、凝集素型(lectin-like)和细胞壁相联型(WAK)等不同的RLK亚家族.这些RLK能够感受多种发育和外界环境胁迫信号, 并在植物对非生物胁迫的响应过程中发挥重要的调控作用.本文结合当今国内外研究进展,简述植物RLK的典型结构域特征,详细介绍多种RLK在植物逆境信号识别与转导中发挥的作用,同时对RLK在非生物胁迫应答中的具体作用机制进行了探讨. 相似文献
992.
许多核受体属于核转录因子,它们在胞浆合成后快速地转运入核,同时还能够在核浆之间穿梭以行使其特定的生物学功能。核受体的核浆转运主要通过核膜上的核孔复合体,依靠运输载体Importins和Exportins介导以及Ran-GDP提供能量。现对糖皮质激素受体(GR)、雄激素受体(AR)和雌激素受体(ER)等核受体在核浆穿梭转运和调控机制等方面的研究进展进行综述,同时也介绍我们实验室最近发现的视黄素X受体(RXR)核浆穿梭转运的新功能。 相似文献
993.
14-3-3蛋白与植物细胞信号转导 总被引:2,自引:0,他引:2
14-3-3蛋白通过直接蛋白质-蛋白质相互作用对植物代谢关键酶、质膜H^+ -ATP酶等发挥广泛调节作用。越来越多证据显示14-3-3蛋白通过与转录因子和其他信号分子结合参与调控植物细胞信号转导。对植物细胞中14-3-3蛋白调控信号转导途径,尤其是植物细胞对胁迫响应的调控机制进行了综述。 相似文献
994.
植物激素信号之间的相互作用 总被引:6,自引:0,他引:6
植物激素问的相互作用对植物的正常发育来说非常重要。不同植物激素之间存在相互协同、对抗和因果等关系,以精细调控植物的发育和对环境的反应等,植物激素信号之间的相互作用已成为植物细胞中不同信号间相互作用机制研究的模式系统。现对不同植物激素在生物合成、代谢、运输和信号转导途径等层次上的相互作用进行综述,并对这一领域的研究进行了总结和展望。 相似文献
995.
996.
生长激素受体(growth hormone receptor,GHR)是细胞因子/造血因子受体超级家族的一员。它通过二聚体的形式和生长激素(growth hormone,GH)相结合,然后诱发Janus激酶2(Janus kinase 2,JAK2)等细胞因子酪氨酸磷酸化并通过4条不同的途径将信号传入细胞内从而产生一系列的生理效应。现在了解GHR的结构特征、组织分布的基础上,对其介导的信号转导途径作进一步的阐明。 相似文献
997.
Dimitri A. Svistunenko 《BBA》2005,1707(1):127-155
The reaction between hydroperoxides and the haem group of proteins and enzymes is important for the function of many enzymes but has also been implicated in a number of pathological conditions where oxygen binding proteins interact with hydrogen peroxide or other peroxides. The haem group in the oxidized Fe3+ (ferric) state reacts with hydroperoxides with a formation of the Fe4+=O (oxoferryl) haem state and a free radical primarily located on the π-system of the haem. The radical is then transferred to an amino acid residue of the protein and undergoes further transfer and transformation processes. The free radicals formed in this reaction are reviewed for a number of proteins and enzymes. Their previously published EPR spectra are analysed in a comparative way. The radicals directly detected in most systems are tyrosyl radicals and the peroxyl radicals formed on tryptophan and possibly cysteine. The locations of the radicals in the proteins have been reported as follows: Tyr133 in soybean leghaemoglobin; αTyr42, αTrp14, βTrp15, βCys93, (αTyr24−αHis20), all in the α- and β-subunits of human haemoglobin; Tyr103, Tyr151 and Trp14 in sperm whale myoglobin; Tyr103, Tyr146 and Trp14 in horse myoglobin; Trp14, Tyr103 and Cys110 in human Mb. The sequence of events leading to radical formation, transformation and transfer, both intra- and intermolecularly, is considered. The free radicals induced by peroxides in the enzymes are reviewed. Those include: lignin peroxidase, cytochrome c peroxidase, cytochrome c oxidase, turnip isoperoxidase 7, bovine catalase, two isoforms of prostaglandin H synthase, Mycobacterium tuberculosis and Synechocystis PCC6803 catalase-peroxidases. 相似文献
998.
Ultraviolet reflectance of plumage for parent-offspring communication in the great tit (Parus major)
Ultraviolet (UV) reflectance has been implicated in mate selection.Yet, in some bird species the plumage of young varies in UVreflectance already in the nest and long before mate choiceand sexual selection come into play. Most birds molt the juvenilebody plumage before reaching sexual maturity, and thus, someconspicuous traits of the juvenile body plumage may rather haveevolved by natural selection, possibly via predation or parentalpreference. This second hypothesis is largely untested and predictsa differential allocation of food between fledging and totalindependence, which is a time period of 2–3 weeks whereoffspring mortality is also highest. Here, we test the predictionthat parents use the individual variation in UV reflectanceamong fledglings for differential food allocation. We manipulatedUV reflectance of the plumage of fledgling great tits Parusmajor by treating chest and cheek feathers with a lotion thateither did or did not contain UV blockers and then recordedfood allocation by parents in an outdoor design simulating postfledgingconditions. The visible spectrum was minimally affected by thistreatment. Females were found to feed UV-reflecting offspringpreferentially, whereas males had no preference. It is the firstevidence showing that the UV reflectance of the feathers ofyoung birds has a signaling function in parent–offspringcommunication and suggests that the UV traits evolved via parentalpreference. 相似文献
999.
1000.
Se Whan Park Moon Gyu Chung Hwa Young Lee Jeong Yoon Kim Young Ha Rhee 《Journal of microbiology (Seoul, Korea)》2008,46(6):662-669
An efficient strategy for the expression and secretion of extracellular polyhydroxybutyrate depolymerase (PhaZ1) of Paucimonas lemoignei in Escherichia coli was developed by employing the signal peptide of PhaZ1 and a truncated ice nucleation protein anchoring motif (INPNC). Directly
synthesized mature form of Phaz1 was present in the cytoplasm of host cells as inclusion bodies, while a construct containing
Phaz1 and its own N-terminal signal peptide (PrePhaz1) enabled the secretion of active Phaz1 into the extracellular medium.
However, the PrePhaz1 construct was harmful to the host cell and resulted in atypical growth and instability of the plasmid
during the cultivation. In contrast, INPNC-Phaz1 and INPNC-PrePhaz1 fusion constructs did not affect growth of host cells.
INPNC-Phaz1 was successfully displayed on the cell surface with its fusion form, but did not retain Phaz1 activity. In the
case of INPNC-PrePhaz1, the initially synthesized fusion form was separated by precise cleavage of the signal peptide, and
active Phaz1 was consequently released into the culture medium. The amount of Phaz1 derived from E. coli (INPNC-PrePhaz1) was almost twice as great as that directly expressed from E. coli (PrePhaz1), and was predominantly (approximately 85%) located in the periplasm when cultivated at 22°C but was efficiently
secreted into the extracellular medium when cultivated at 37°C. 相似文献