谷子和狗尾草核型分析

作者研究了我国谷子(Setaria italica Beauv.)和狗尾草的核型与Giemsa带,两者核型基本相同,均为2n=18=14m+2sm+2st(SAT)。带型亦相近,另外在谷子和狗尾草中都发现有四倍体。     

谷子显性雄性不育基因“Ms~（ch）”的细胞质转换

通过种间杂交和连续置换回交,选育出具有轮生狗尾草（Ｓ,ｖｅｒｔｉｃｉｌｌａｔａ（Ｌ．）Ｂｅａｕｖ．）细胞质的谷子（Ｓｅｔａｒｉａｉｔａｌｉｃａ（Ｌ．）Ｂｅａｕｖ．）核质杂种,以带有上位基因Ｒｆ的显性核不育植株为父本与此核质杂种杂交,已将显性核不育基因导入轮生狗尾草细胞质中,从其分离后代中选出了具有显性核不育基因的新核质杂种,为谷子的三系选育和细胞质研究创造了新工具,也为核互作杂优利用增加了核质互作优势新机制。     

Variation,geographical distribution and genetical analysis of esterase isozymes in foxtail millet,Setaria italica (L.) P. Beauv.

Summary The esterase isozymes of 432 strains of foxtail millet, Setaria italica (L.) P. Beauv., collected from different areas throughout Eurasia, were investigated by gel isoelectric focusing. Five phenotypes were recognized, based on the combination of five major activity bands. Cross experiments among different phenotypes revealed these isozymes to be controlled by two codominant alleles and a null allele on the locus, Est-1, and three codominant alleles on another independent locus, Est-2. On locus Est-1, 388 strains had Est-1 ^a, 41 had Est-1 ^b and three had Est-1 ^null alleles. Est-1 ^a was widely distributed throughout Eurasia, while the distribution of Est-1 ^b and Est-1 ^null was distinctly restricted. On locus Est-2, 417 strains had Est-2 ^a, nine had Est-2 ^b and six had Est-2 ^c alleles. Est-2 ^a was widely distributed throughout Asia to Czechoslovakia, but was not detected in the western part of Europe. Est-2 ^b was found in all of the strains from the western part of Europe and in one of the Indian strains. Est-2 ^c was rarely found in Japan and China. The distribution of Est-2 ^a and -2 ^b might indicate some degree of phylogenetic differentiation between the Asian and the European strains. Polymorphism in both loci was observed only in Chinese strains.Contribution No. 30 from the Plant Germ-plasm Institute, Faculty of Agriculture, Kyoto University, Kyoto, Japan     

谷子PAL基因家族全基因组的鉴定和表达分析

苯丙氨酸解氢酶(phenylalanine ammonia-lyase,PAL)基因家族参与苯丙烷类代谢过程,通过调控植物抗病次生物质的合成在植物抗逆反应中发挥重要作用。为明确谷子PAL基因家族在逆境胁迫下的表达规律,该研究利用生物信息学方法对谷子PAL基因家族进行鉴定和表达分析。结果表明:谷子具有11个PAL基因,在进化树中可分为3个亚家族,SiPAL7独自进化为一支。通过构建蛋白结构域发现PAL基因家族成员均含有保守的PAL结构域。启动子分析显示,PAL基因含有应答激素、逆境胁迫等多种因子的顺式作用元件,说明PAL基因广泛参与不同生物学调控过程。RT-qPCR结果显示,谷子PAL基因家族多为诱导型表达,不同光照条件下PAL基因表达量变化明显,不同基因具有不同响应模式,说明谷子PAL基因家族在参与光调节反应中发挥重要作用。谷子PAL基因高度保守,广泛响应不同非生物胁迫,具有表达特异性。该研究结果为揭示PAL基因家族在调节谷子抗性及胁迫应答过程中的作用提供了参考。     

Construction of RFLP-based maps of foxtail millet, Setaria italica (L.) P. Beauv.

 An RFLP-based map consisting of 160 loci was constructed in an intervarietal cross of foxtail millet [Setaria italica (L.) P. Beauv.], Longgu 25×Pagoda Flower Green. The map comprises nine linkage groups, which were aligned with the nine foxtail millet chromosomes using trisomic lines, and spans 964 cM. The intraspecific map was compared to an interspecific map, constructed in a S. italica×S. viridis cross. Both the order of the markers and the genetic distances between the loci were highly conserved. Deviations from the expected 1 : 2 : 1 Mendelian segregation ratios were observed in both the intra- and inter-specific populations. The segregation data indicate that chromosome VIII in the Longgu 25×Pagoda Flower Green cross carries a gene that strongly affects gamete fertility. Received: 18 December 1996 / Accepted: 4 August 1997     

MALDI mass sequencing and characterization of filarialglutathione-S-transferase

Glutathione-S-transferase has been detected in the somatic extract and excretory-secretory products of different life stages of Setaria cervi, a bovine filarial parasite. The enzyme was subjected to MALDI-TOF followed by mass spectrometry and the nearest match found was Pleuronectes platessa GST. Molecular mass of the purified enzyme was approximately 26 kDa as determined by SDS-PAGE and MALDI-TOF. Setaria cervi GST exhibited high activity towards 1-chloro-2,4-dinitrobenzene and ethacrynic acid. Kinetic analysis with respect to 1-chloro-2,4-dinitrobenzene and glutathione as substrate revealed a K(m) of 2.22 mM and 0.61 mM, respectively. The activity was inhibited significantly by Cibacron blue and alpha-tocopherol.     

Setaria cervi: kinetic studies of filarial glutathione synthetase by high performance liquid chromatography

The bovine filarial worm Setaria cervi was found to have abundance of glutathione synthetase (GS; EC 6.3.2.3) activity, the enzyme being involved in catalysing the final step of glutathione (GSH) biosynthesis. A RP-HPLC method involving precolumn derivatization with o-phthalaldehyde has been followed for the estimation of GS activity in crude filarial preparations. Subcellular fractionation of the enzyme was undertaken and it was confirmed to be a soluble protein residing mainly in cytosolic fraction. Attempts to determine the Km value for L-gamma-glutamyl-L-cysteine gave a distinctly nonlinear double-reciprocal plot in which data obtained at relatively high dipeptide concentrations (>1 mM) extrapolate to a Km value of about 400 microM whereas data obtained at lower concentrations (<0.1 mM) extrapolate to a value of about 33 microM. Km was determined to be around 950 and 410 microM for ATP and glycine, respectively. The effect of various amino acids was studied on enzyme activity at 1mM concentration. L-cystine caused a significant enzyme inhibition of 11%. Preincubation with N-ethylmaleimide also resulted in significant inhibition of GS activity.     

谷子肌动蛋白基因的克隆及序列分析

以谷子 (Setariaitalica)为材料 ,提取总RNA。根据植物肌动蛋白基因编码区的两端的保守序列设计了简并引物 ,用 5’RACE方法扩增出了谷子肌动蛋白基因编码区序列。以豌豆肌动蛋白cDNA作探针进行的Southern杂交分析表明扩增出了目的基因。将所获得的片段克隆到T载体后进行测序 ,序列分析结果表明 :谷子肌动蛋白基因的编码区长 1 1 3 1个核苷酸 ,编码了 3 77个氨基酸 ;所得序列 (命名为MIAc)与GenBank中注册的肌动蛋白基因序列的相似性均在 6 0 %以上 ,与其它肌动蛋白氨基酸序列的相似性达 89%以上。根据高等植物肌动蛋白序列相似性重建了进化树 ,表明谷子肌动蛋白与水稻肌动蛋白异型体RAc2和RAc3之间的亲缘关系最为密切 ,在进化过程中分化时间最为接近     

Setaria equina: In vivo effect of diethylcarbamazine citrate on microfilariae in albino rats

Although diethylcarbamazine citrate (DEC) is successful drug in eliminating human filariasis, yet, its mode of action is still debatable. Herein, the effect of DEC to treat albino rats infected with the animal filarial parasite Setaria equina was tested. Microfilarial (mf) counts and sections from liver, lung, kidney as well as spleen were investigated at different time points after treatment by light microscopy. After 45 and 300 min of treatment, a significant decrease in blood mf was observed accompanied by adherence of degenerated mf to both kupffer cells and leukocyte in liver sections. In lung sections, loss of sheath was observed at 45 min, while degeneration was observed at later time points. In kidney sections, more mf counts and less matrix were observed in the glomeruli at all time points after treatment. Degenerated mf were observed in spleen sections only at, late time point, 480 min after treatment. In conclusion, one of the possible mechanisms by which DEC reduces blood microfilarial count is trapping larvae in organs and killing them through cellular adherence.     

Upregulation of bundle sheath electron transport capacity under limiting light in C4 Setaria viridis

C₄ photosynthesis is a biochemical pathway that operates across mesophyll and bundle sheath (BS) cells to increase CO₂ concentration at the site of CO₂ fixation. C₄ plants benefit from high irradiance but their efficiency decreases under shade, causing a loss of productivity in crop canopies. We investigated shade acclimation responses of Setaria viridis, a model monocot of NADP-dependent malic enzyme subtype, focussing on cell-specific electron transport capacity. Plants grown under low light (LL) maintained CO₂ assimilation rates similar to high light plants but had an increased chlorophyll and light-harvesting-protein content, predominantly in BS cells. Photosystem II (PSII) protein abundance, oxygen-evolving activity and the PSII/PSI ratio were enhanced in LL BS cells, indicating a higher capacity for linear electron flow. Abundances of PSI, ATP synthase, Cytochrome b₆f and the chloroplast NAD(P)H dehydrogenase complex, which constitute the BS cyclic electron flow machinery, were also increased in LL plants. A decline in PEP carboxylase activity in mesophyll cells and a consequent shortage of reducing power in BS chloroplasts were associated with a more oxidised plastoquinone pool in LL plants and the formation of PSII – light-harvesting complex II supercomplexes with an increased oxygen evolution rate. Our results suggest that the supramolecular composition of PSII in BS cells is adjusted according to the redox state of the plastoquinone pool. This discovery contributes to the understanding of the acclimation of PSII activity in C₄ plants and will support the development of strategies for crop improvement, including the engineering of C₄ photosynthesis into C₃ plants.