A self-contained system for the field production of plant recombinant interleukin-10

The production of pharmaceutical proteins in plants is creating a broad spectrum of new high-value traits in traditional crop species. As the production of these recombinant proteins moves from bench to field scale, containment and the presence of unwanted secondary metabolites are significant practical issues. We have developed a hybrid male-sterile low-alkaloid tobacco (MSLA) production platform. Recombinant protein is produced in leaves that are harvested prior to flowering. If considered for direct in vivo mammalian use the low-alkaloid background genotype addresses concerns about nicotine, and male sterility further reduces the risk of gene leakage. We have applied this system to the production of human interleukin-10 (phIL-10), a contra-inflammatory cytokine with potential application in the treatment of inflammatory bowel disease and autoimmune diseases. Transgenic low-alkaloid tobacco lines properly assembled a biologically active phIL-10 homodimer. Hybrids made by crossing a single homozygous high-expressing phIL-10 line with a MSLA female were field tested in a high density production system and harvested after 30 days. Recombinant phIL-10 yields were found to be similar in the hybrids and the homozygous control. MSLA tobacco is a practical, self-contained system for the production of plant recombinant proteins.     

苎麻雄性不育系生化代谢和育性遗传研究

用不同温度和日长处理盆栽材料,测试苎麻雄性不育系的温光反应;于雌雄性器官发育期取盆栽植株顶部展开叶往下数第7叶,分析不育系的生化代谢;根据杂交及自交后代育性分离情况,鉴定不育系的不育性遗传方式.结果如下高温加速营养生长,而短日促进生殖生长,短日高温明显加快不育系的发育进度,但高温的促进作用随日长增加而减弱,以至消失.不育系的叶片粗蛋白质、氨基酸含量比可育系减少,尤其是天门冬氨酸、谷氨酸、甘氨酸、胱氨酸、缬氨酸、苯丙氨酸和精氨酸减少明显,但游离脯氨酸含量增加.这些物质代谢的变化,可能是导致苎麻雄性不育的原因.不育系GS14-1、SS370、GSA-2、GS15-8和SS387等的不育性遗传与1对相对性状的遗传方式相符,已找到不育系的保持系和恢复系.     

水稻ＣＭＳ—ＷＡ育性恢复基因的定位

在由227个组合组成的珍汕97A×（珍汕97B×密阳46）F     

Effect of nitrogen,phosphorus and potassium on spikelet sterility induced by low temperature at the reproductive stage of rice

Spikelet sterility induced by low temperature at the reproductive stage of rice increased further with the increase of nitrogen supply. Spikelet sterility in Fujisaka-5 did not increase due to low temperature when nitrogen supply was increased from 10 to 40 ppm and at 80 ppm nitrogen supply it was less affected than IR36. Total nitrogen content in the leaves increased with the increase of nitrogen supply and was forced to be associated with the spikelet sterility induced by low temperature. Based on auricle distance between the last two leaves, the most sensitive stage to low temperature damage differed in Fujisaka-5 and IR36. Spikelet sterility induced by low temperature for 10 days was very high in both the varieties and the effect of nitrogen was not clear.The effect of phosphorus on the spikelet sterility induced by low temperature at reproductive stage was not clear except that at the highest phosphorus (P) level (10 ppm) the spikelet sterility increased both in Fujisaka-5 and IR36.Spikelet sterility induced by low temperature at the reproductive stage of rice decreased with the increase of Potassium (K) supply in both Fujisaka-5 and IR36. With an increase of potassium supply, nitrogen (N) content decreased in the leaves and panicles and spikelet sterility induced by low temperature decreased with an increase of the K to N ratio in the leaves and panicles. The results suggest that potassium might play a major role to counteract the low temperature damage at the reproductive stage of rice.     

Characterization and mapping of a novel mutant sms1 (senescence and male sterility 1) in rice

Plant senescence plays diverse important roles in development and environmental responses.However,the molecular basis of plant senescence is remained largely unknown.A rice spontaneous mutant with the character of early senescence and male sterility (sms) was found in the breeding line NT10-748.In order to identify the gene SMS1 and the underlying mechanism,we preliminarily analyzed physiological and biochemical phenotypes of the mutant.The mutant contained lower chlorophyll content compared with the wild t...     

Male-sterile chicory cybrids obtained by intergeneric protoplast fusion

Male-sterile chicory plants were obtained by fusion of chicory mesophyll protoplasts and hypocotyl protoplasts derived from male-sterile sunflower plants. The protoplasts of both species were fused by the PEG method and the products were selected manually and cultivated at very low density in a liquid medium. Three to twenty percent of the heterokaryocytes divided and evolved into microcalli, then into calli where budding could be induced. The mitochondrial genome of ten male-sterile or totally sterile plants was studied. Restriction endonuclease profiles of mitochondrial DNA and molecular hybridization with specific genes of the mitochondrial genome used as probes indicated that mitochondrial DNA rearrangement had occurred between sunflower and chicory and the intensity of the rearrangements correlated with the degree of sterility of the different plants.     

The relationship between postmating reproductive isolation and reinforcement in Phlox

The process of speciation involves the accumulation of reproductive isolation (RI) between diverging lineages. Selection can favor increased RI via the process of reinforcement, whereby costs to hybridization impose selection for increased prezygotic RI. Reinforcement results in phenotypic divergence within at least one taxon, as a result of costly hybridization between sympatric taxa. The strength of selection driving reinforcement is determined by the cost of hybridization and the frequency of hybridization. We investigated the cost of hybridization by quantifying postmating RI barriers among Phlox species that comprise one of the best‐studied cases of reinforcement. We determined if the strength of RI differs among lineages that have and have not undergone reinforcement, how much variability there is within species in RI, and whether RI is associated with phylogenetic relatedness. We found high RI for the species that underwent phenotypic divergence due to reinforcement; however, RI was also high between other species pairs. We found extensive variability in RI among individuals within species, and no evidence that the strength of RI was associated with phylogenetic relatedness. We suggest that phenotypic divergence due to reinforcement is associated with the frequency of hybridization and introgression, and not the cost of hybridization in this clade.