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131.
无蹼壁虎繁殖生态生物学研究 总被引:3,自引:0,他引:3
壁虎科 (Gekkonidae)动物以恒定窝卵数作为其主要生殖策略 ,多疣壁虎 (Gekkojaponicus)以较高产卵频率和较大雌体 (卵大一些 )在种群中的比例 (计翔等 ,1991a)作为其又一生殖策略。本文在前人研究的基础上 ,对无蹼壁虎 (G .swinhonis)的繁殖生态生物学做进一步研究。1 研究方法1 1 野外观察时间及地点1993~ 1997年 ,在江苏省云龙山上的旧碉堡内 ,观察记录壁虎产卵、孵化等情况。1 2 饲 养1995、 1996、 1998和 1999年 ,参照计翔等 (1991b)方法 ,用木箱和纸箱饲养壁虎。每箱内饲养 1对成体壁虎 ,以… 相似文献
132.
Tsai WC Lee PF Chen HI Hsiao YY Wei WJ Pan ZJ Chuang MH Kuoh CS Chen WH Chen HH 《Plant & cell physiology》2005,46(7):1125-1139
In this study, we isolated and characterized the function of a GLOBOSA/PISTILLATA-like gene, PeMADS6, from a native Phalaenopsis species, P. equestris. Southern blot analysis showed PeMADS6 as a single copy in the Phalaenopsis genome. Results of the determination of temporal and spatial expression showed that PeMADS6 was expressed and thus participated in the development of the sepals, petals, labellum and column in Phalaenopsis. Further confirmation of the expression pattern of PeMADS6 was carried out with in situ hybridization. Repressed expression of PeMADS6 in the orchid ovary was found to be pollination regulated, which suggests that the gene may have an inhibitory effect on the development of the ovary or ovule. In addition, auxin acted as the candidate signal to regulate the repression of PeMADS6 expression in the ovary. Furthermore, the flowers of transgenic Arabidopsis plants ectopically overexpressing PeMADS6 showed the morphology of petaloid sepals, with a 3- to 4-fold increase in flower longevity. Concomitantly, delayed fruit maturation was also observed in the transgenic Arabidopsis, which is consistent with the inhibitory effect of PeMADS6 on the development of the ovary. Thus, as a B-function gene, PeMADS6, not only specifies floral organ identity but has functions in flower longevity and ovary development in orchids. 相似文献
134.
Hai-Bin?Zhang Ying?Zhang Cheng?ChenEmail author Yu-Qing?Li Chi?Ma Zhao-Jun?Wang 《Apoptosis : an international journal on programmed cell death》2016,21(10):1082-1093
Apoptosis and degeneration coming mainly from chondrocytes are important mechanisms in the onset and progression of osteoarthritis. Specifically, advanced glycation end products (AGEs) play an important role in the pathogenesis of osteoarthritis. Pioglitazone, a peroxisome proliferator-activated receptor γ (PPARγ) agonist has a protective effect on cartilage. This study aims to evaluate the effect of pioglitazone on AGEs-induced chondrocyte apoptosis and degeneration and their underlying mechanism. The in vitro study shows that AGEs induce cleavage of caspase-3 and PARP, up-regulate MMP-13 expression, enhance chondrocyte apoptosis and down-regulate PPARγ expression in human primary chondrocytes, which is reversed by pioglitazone. Furthermore, AGEs activate phosphorylation of Erk, JNK, and p38, and pioglitazone reverses AGEs-induced phosphorylation of Erk and p38. AGEs-induced degradation of IκBα and translocation of nuclear NF-κB p65 is reversed by pioglitazone. Pretreatment of chondrocytes with SB202190 (p38 inhibitor), SP600125 (JNK inhibitor) and BAY-11-7082 (NF-κB inhibitor) inhibit AGEs-induced apoptosis and degeneration. In vivo experiments suggest that pioglitazone reverses AGEs-induced cartilage degeneration and apoptosis in a mouse model, as demonstrated by HE and Safranin O staining, immunohistochemical analyses of Type II collagen (Col II), metalloproteinases (MMPs) and caspase-3. These findings suggest that pioglitazone, a PPARγ agonist, inhibits AGEs-induced chondrocytes apoptosis and degeneration via suppressing the activation of MAPK and NF-κB. 相似文献
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137.
Jie Jiang Li-Xin Huang Feng Chen Cheng-Wang Sheng Qiu-Tang Huang Zhao-Jun Han Chun-Qing Zhao 《Insect Science》2021,28(3):757-768
The resistance to dieldrin gene (RDL) encodes the primary subunit of the insect ionotropic γ-aminobutyric acid (GABA) receptor (GABAR), which is the target of phenylpyrazole and isoxazoline insecticides. The splice variants in exons 3 and 6 of RDL, which have been widely explored in many insects, modulate the agonist potency of the homomeric RDL GABAR and potentially play an important role in the development of insects. In the present study, four splice variants of exon 9 were identified in RDL of the small brown planthopper, Laodelphax striatellus (LsRDL), resulting in LsRDL-9a, LsRDL-9a’, LsRDL-9b, and LsRDL-9c. LsRDL-9a has one more amino acid (E, glutamic acid) compared with LsRDL-9a’, and LsRDL-9b lacked two amino acids and had seven different amino acids compared with LsRDL-9c. Two-electrode voltage-clamp recording on LsRDLs expressed in Xenopus oocytes showed that alternative splicing of exon 9 has significant impact on LsRDL sensitivity to the agonists GABA and β-alanine, whereas no significant difference was observed in the potencies of the non-competitive antagonists (NCAs) ethiprole and fluralaner on the splice variants. Our results suggest that alternative splicing of RDL exon 9 broadens functional capabilities of the GABAR in L. striatellus by influencing the action of GABA. 相似文献
138.
Zhao-Jun Wei Miao Yu Shun-Ming Tang Yong-Zhu Yi Gui-Yun Hong Shao-Tong Jiang 《Molecular biology reports》2011,38(2):1121-1127
Prothoracicotropic hormone (PTTH) is one of key players in regulation of insect growth, molting, metamorphosis, diapause,
and is expressed specifically in the two pairs of lateral PTTH-producing neurosecretory cells in the brain. Analysis of cis-regulatory elements of the PTTH promoter might elucidate the regulatory mechanism controlling PTTH expression. In this study,
the PTTH gene promoter of Bombyx mori (Bom-PTTH) was cloned and sequenced. The cis-regulatory elements in Bom-PTTH gene promoter were predicted using Matinspector software, including myocyte-specific enhancer
factor 2, pre-B-cell leukemia homeobox 1, TATA box, etc. Transient transfection assays using a series of fragments linked
to the luciferase reporter gene indicated that the fragment spanning −110 to +33 bp of the Bom-PTTH promoter showed high ability
to support reporter gene expression, but the region of +34 to +192 bp and −512 to −111 bp repressed the promoter activity
in the BmN and Bm5 cell lines. Electrophoretic mobility shift assays demonstrated that the nuclear protein could specifically
bind to the region spanning −124 to −6 bp of the Bom-PTTH promoter. Furthermore, we observed that the nuclear protein could
specifically bind to the −59 to −30 bp region of the Bom-PTTH promoter. A classical TATA box, TATATAA, localized at positions
−47 to −41 bp, which is a potential site for interaction with TATA box binding protein (TBP). Mutation of this TATA box resulted
in no distinct binding band. Taken together, TATA box was involved in regulation of PTTH gene expression in B. mori. 相似文献