The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These g...The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These genes encode polytopic membrane proteins that feature an MtN3/saliva domain, also known as a PQ loop repeat, The rice MtN3/saliva/SWEET gene family consists of 21 members and is among the largest families in sequenced organisms. Accumulating data suggest that these genes are involved in multiple physiological processes, including reproductive development, senescence, environmental adaptation, and host-pathogen interaction, in different species. In rice, some members of the family, including Xa13/Os8N3/OsSWEET11, which is essential for reproductive development, are used by the pathogenic bacterium Xanthomonas oryzae pv. oryzae to invade its host. Emerging data have also revealed that at least some MtN3/saliva/SWEET-type proteins may regulate different physiological processes by facilitating ion transport via interaction with ion transporters or as sugar transporters. The accumulating knowledge about MtN3/saliva/SWEET- type genes will help to elucidate the molecular bases of their function in different organisms.展开更多
The first seedling or all-stage resistance （R） R gene against stripe rust isolated from Moro wheat （Triticum aes- tivum L.） using a map-based cloning approach was identified as Yr10. Clone 4B of this gene encodes ...The first seedling or all-stage resistance （R） R gene against stripe rust isolated from Moro wheat （Triticum aes- tivum L.） using a map-based cloning approach was identified as Yr10. Clone 4B of this gene encodes a highly evolutionary- conserved and unique CC-NBS-LRR sequence. Clone 4E, a homolog of Yr10, but lacking transcription start site （TSS） and putative TATA-box and CAAT-box, is likely a non-expressed pseudogene. Clones 4B and 4E are 84% identical and divergent in the intron and the LRR domain. Gene silencing and transgenesis were used in conjunction with inoculation with differen- tially avirulent and virulent stripe rust strains to demonstrate Yr10 functionality. The Yr10 CC-NBS-LRR sequence is unique among known CC-NBS-LRR R genes in wheat but highly conserved homologs （E = 0.0） were identified in Aegilops tauschii and other monocots including Hordeum vulgare and Brachypodium distachyon. Related sequences were also identified in genomic databases of maize, rice, and in sorghum. This is the first report of a CC-NBS-LRR resistance gene in plants with limited homologies in its native host, but with numerous homologous R genes in related monocots that are either host or non-hosts for stripe rust. These results represent a unique example of gene evolution and dispersion across species.展开更多
Androgen receptor （AR） gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat （CAG and GGN） length polymorphisms have been an additional subject ...Androgen receptor （AR） gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat （CAG and GGN） length polymorphisms have been an additional subject of interest and controversy among geneticists. The polymorphic variations in triplet repeats have been associated with a number of disorders, but at the same time contradictory findings have also been reported. Further, studies on the same disorder in different populations have generated different results. Therefore, combined analysis or review of the published studies has been of much value to extract information on the significance of variations in the gene in various clinical conditions. AR genetics has been reviewed extensively but until now review articles have focused on individual clinical categories such as androgen insensitivity, male infertility, prostate cancer, and so on. We have made the first effort to review most the aspects of AR genetics. The impact of androgens in various disorders and polymorphic variations in the AR gene is the main focus of this review. Additionally, the correlations observed in various studies have been discussed in the light of in vitro evidences available for the effect of AR gene variations on the action of androgens.展开更多
In the urban labor market, the rural labor force can choose whether to become self- employed or work for wages depending on their stock of human capital and local labor market conditions. A simple Mincer earnings regr...In the urban labor market, the rural labor force can choose whether to become self- employed or work for wages depending on their stock of human capital and local labor market conditions. A simple Mincer earnings regression shows that the rate of return to schooling for wage earners is two percentage points higher than that for the self-employed. After correcting for bias in sample selection, the expanded Mincer earnings equation estimated the rate of return to schooling for wage earners at between 5.3 and 6.8 percent. From the standpoint of training, we found that the simplest form of training, short-term training and formal training played an important role in promoting migrant workers’ repeat mobility. However, the simplest form of training did not have a significant effect on earnings,whereas short-term and formal training played an important determining role in this respect. Moreover, rights protection issues such as wage arrears also had an important effect on migrant workers’ repeat mobility. In handling heterogeneity and endogenous educational variables among migrant workers, the authors found that the years of schooling of the parents of migrant workers were not an ideal instrumental variable.展开更多
Pure laparoscopic hepatectomy is a less invasive procedure than conventional open hepatectomy for the resection of hepatic lesions. Increases in experiences with the technique, in combination with advances in technolo...Pure laparoscopic hepatectomy is a less invasive procedure than conventional open hepatectomy for the resection of hepatic lesions. Increases in experiences with the technique, in combination with advances in technology, have promoted the popularity of pure laparoscopic hepatectomy. However, indications for usage and potential contraindications of the procedure remain unresolved. The characteristics and specific advantages of the procedure, especially for hepatocellular carcinoma(HCC) patients with chronic liver diseases,are reviewed and discussed in this paper. For cirrhotic patients with liver tumors, pure laparoscopic hepatectomy minimizes destruction of the collateral blood and lymphatic flow from laparotomy and mobilization, and mesenchymal injury from compression. Therefore, pure laparoscopic hepatectomy has the specific advantage of minimal postoperative ascites production that leads to lowering the risk of disturbance in water or electrolyte balance and hypoproteinemia. It minimizes complications that routinely trigger postoperative serious liver failure. Under adequate patient positioning and port arrangement, the partial resection of the liver in the area of subphrenic space, peri-inferior vena cava area or next to the attachment of retro-peritoneum is facilitated in pure laparoscopic surgery by providing good vision and manipulation in the small operative field.Furthermore, the features of reduced post-operative adhesion, good vision, and manipulation within the small area between the adhesions make this procedure safer in the context of repeat hepatectomy procedures.These improved features are especially advantageous for patients with liver cirrhosis and multicentric and/or metachronous HCCs.展开更多
Pentatricopeptide repeat （PPR） proteins, charac- terized by tandem arrays of a 35 amino acid motif, have been suggested to play central and broad roles in modulating the expression of organelle genes in plants. Howe...Pentatricopeptide repeat （PPR） proteins, charac- terized by tandem arrays of a 35 amino acid motif, have been suggested to play central and broad roles in modulating the expression of organelle genes in plants. However, the molecular mechanisms of most rice PPR genes remains unclear. In this paper, we isolated and characterized a temperature-conditional virescent mutant, OsV4, in rice （Oryza sativa cultivar Jiahual （WT, japonica rice variety））. The mutant displays albino phenotype and abnormal chloroplasts at the three leaf stage, which gradually turns green after the four leaf stage at a low temperature （20℃）. But the mutant always develops green leaves and well-developed chloroplasts at a high temperature （32℃）. Genetic and molecular analyses uncovered that OsV4 encodes a novel chloroplast-targeted PPR protein including four PPR motifs. Further investigations show that the mutant phenotype is associated with changes in chlorophyll content and chloroplast development. The OsV4 transcripts only accumulate to high levels in young leaves, indicating that its expression is tissue-specific. In addition, transcript levels of some ribosomal components and plastid- encoded polymerase-dependent genes are dramatically re- duced in the albino mutants grown at 20℃. These findings suggest that OsV4 plays an important role during early chloroplast development under cold stress in rice.展开更多
Soybean mosaic virus （SMV） is one of the most broadly distributed diseases worldwide. It causes severe yield loss and seed quality deficiency in soybean （Glycine max （L.） Merr.）. SMV Strain SC14 isolated from Sh...Soybean mosaic virus （SMV） is one of the most broadly distributed diseases worldwide. It causes severe yield loss and seed quality deficiency in soybean （Glycine max （L.） Merr.）. SMV Strain SC14 isolated from Shanxi Province, China, was a newly identified virulent strain and can infect Kefeng No. 1, a source with wide spectrum resistance. In the present study, soybean accessions, PI96983, Qihuang No. 1 and Qihuang No. 22 were identified to be resistant （R） and Nannong 1138-2, Pixianchadou susceptible （S） to SC14. Segregation analysis of PI96983 x Nannong 1138-2 indicated that a single dominant gene （designated as Rsc14） controlled the resistance to SC14 at both V2 and R1 developmental stages. The same results were obtained for the crosses of Qihuang No. 1 × Nannong 1138-2 and Qihuang No. 22 x Nannong 1138-2 as in PI96983 x×Nannong 1138-2 at V2 stage, but at R1 stage, the F1 performed as necrosis （a susceptible symptom other than mosaic）, F2 segregated in a ratio of 1R：2N：IS, and the progenies of necrotic （N） F2 individuals segregated also in R, N and S. It indicated that a single gene （designated as Rsc140, to be different from that of PI96983） controlled the resistance to SC14, its dominance was the same as in PI96983 × Nannong 1138-2 （without symptoms） at V2 stage and not the same at R1 stage. The tightly linked co-dominant simple sequence repeat （SSR） marker Satt334 indicated that all the heterozygous bands were completely corresponding to the necrotic F2 individuals, or all the necrotic F2 individuals were heterozygotes. It was inferred that necrosis might be due to the interaction among SMV strains, resistance genes, genetic background of the resistance genes, and plant development stage. Furthermore, the bulked segregant analysis （BSA） of SSR markers was conducted to map the resistance genes. In F2 of PI96983 × Nannong 1138-2, five SSR markers, Sat_297, Sat_234, Sat_154, Sct_033 and Sat_120, were found closely linked to Rsc14, with genetic distances of展开更多
基金This work was supported by grants from the National Program on the Development of Basic Research in China （2012CB114005）the National Program of High Technology Development of China （2012AA10A303） and the National Natural Science Foundation of China （31100875）No conflict of interest declared.
文摘The MtN3/saliva/SWEET-type genes, existing either alone or in a family group, are found in diverse organisms, from monocellular protozoa to higher eukaryotes, indicating their importance in cellular organisms. These genes encode polytopic membrane proteins that feature an MtN3/saliva domain, also known as a PQ loop repeat, The rice MtN3/saliva/SWEET gene family consists of 21 members and is among the largest families in sequenced organisms. Accumulating data suggest that these genes are involved in multiple physiological processes, including reproductive development, senescence, environmental adaptation, and host-pathogen interaction, in different species. In rice, some members of the family, including Xa13/Os8N3/OsSWEET11, which is essential for reproductive development, are used by the pathogenic bacterium Xanthomonas oryzae pv. oryzae to invade its host. Emerging data have also revealed that at least some MtN3/saliva/SWEET-type proteins may regulate different physiological processes by facilitating ion transport via interaction with ion transporters or as sugar transporters. The accumulating knowledge about MtN3/saliva/SWEET- type genes will help to elucidate the molecular bases of their function in different organisms.
文摘The first seedling or all-stage resistance （R） R gene against stripe rust isolated from Moro wheat （Triticum aes- tivum L.） using a map-based cloning approach was identified as Yr10. Clone 4B of this gene encodes a highly evolutionary- conserved and unique CC-NBS-LRR sequence. Clone 4E, a homolog of Yr10, but lacking transcription start site （TSS） and putative TATA-box and CAAT-box, is likely a non-expressed pseudogene. Clones 4B and 4E are 84% identical and divergent in the intron and the LRR domain. Gene silencing and transgenesis were used in conjunction with inoculation with differen- tially avirulent and virulent stripe rust strains to demonstrate Yr10 functionality. The Yr10 CC-NBS-LRR sequence is unique among known CC-NBS-LRR R genes in wheat but highly conserved homologs （E = 0.0） were identified in Aegilops tauschii and other monocots including Hordeum vulgare and Brachypodium distachyon. Related sequences were also identified in genomic databases of maize, rice, and in sorghum. This is the first report of a CC-NBS-LRR resistance gene in plants with limited homologies in its native host, but with numerous homologous R genes in related monocots that are either host or non-hosts for stripe rust. These results represent a unique example of gene evolution and dispersion across species.
文摘Androgen receptor （AR） gene has been extensively studied in diverse clinical conditions. In addition to the point mutations, trinucleotide repeat （CAG and GGN） length polymorphisms have been an additional subject of interest and controversy among geneticists. The polymorphic variations in triplet repeats have been associated with a number of disorders, but at the same time contradictory findings have also been reported. Further, studies on the same disorder in different populations have generated different results. Therefore, combined analysis or review of the published studies has been of much value to extract information on the significance of variations in the gene in various clinical conditions. AR genetics has been reviewed extensively but until now review articles have focused on individual clinical categories such as androgen insensitivity, male infertility, prostate cancer, and so on. We have made the first effort to review most the aspects of AR genetics. The impact of androgens in various disorders and polymorphic variations in the AR gene is the main focus of this review. Additionally, the correlations observed in various studies have been discussed in the light of in vitro evidences available for the effect of AR gene variations on the action of androgens.
文摘In the urban labor market, the rural labor force can choose whether to become self- employed or work for wages depending on their stock of human capital and local labor market conditions. A simple Mincer earnings regression shows that the rate of return to schooling for wage earners is two percentage points higher than that for the self-employed. After correcting for bias in sample selection, the expanded Mincer earnings equation estimated the rate of return to schooling for wage earners at between 5.3 and 6.8 percent. From the standpoint of training, we found that the simplest form of training, short-term training and formal training played an important role in promoting migrant workers’ repeat mobility. However, the simplest form of training did not have a significant effect on earnings,whereas short-term and formal training played an important determining role in this respect. Moreover, rights protection issues such as wage arrears also had an important effect on migrant workers’ repeat mobility. In handling heterogeneity and endogenous educational variables among migrant workers, the authors found that the years of schooling of the parents of migrant workers were not an ideal instrumental variable.
文摘Pure laparoscopic hepatectomy is a less invasive procedure than conventional open hepatectomy for the resection of hepatic lesions. Increases in experiences with the technique, in combination with advances in technology, have promoted the popularity of pure laparoscopic hepatectomy. However, indications for usage and potential contraindications of the procedure remain unresolved. The characteristics and specific advantages of the procedure, especially for hepatocellular carcinoma(HCC) patients with chronic liver diseases,are reviewed and discussed in this paper. For cirrhotic patients with liver tumors, pure laparoscopic hepatectomy minimizes destruction of the collateral blood and lymphatic flow from laparotomy and mobilization, and mesenchymal injury from compression. Therefore, pure laparoscopic hepatectomy has the specific advantage of minimal postoperative ascites production that leads to lowering the risk of disturbance in water or electrolyte balance and hypoproteinemia. It minimizes complications that routinely trigger postoperative serious liver failure. Under adequate patient positioning and port arrangement, the partial resection of the liver in the area of subphrenic space, peri-inferior vena cava area or next to the attachment of retro-peritoneum is facilitated in pure laparoscopic surgery by providing good vision and manipulation in the small operative field.Furthermore, the features of reduced post-operative adhesion, good vision, and manipulation within the small area between the adhesions make this procedure safer in the context of repeat hepatectomy procedures.These improved features are especially advantageous for patients with liver cirrhosis and multicentric and/or metachronous HCCs.
基金supported by Natural Science Foundation of China (no. 30971552)Shanghai Municipal Education Commission of China (no. 14YZ076)+2 种基金Shanghai Municipal Science and Technology Commission of China (10DZ2271800, 12ZR1422000)Leading Academic Discipline Project of Shanghai Municipal Education Commission (no. J50401)the Food Safety and Nutrition Program of Shanghai Normal University (DXL123)
文摘Pentatricopeptide repeat （PPR） proteins, charac- terized by tandem arrays of a 35 amino acid motif, have been suggested to play central and broad roles in modulating the expression of organelle genes in plants. However, the molecular mechanisms of most rice PPR genes remains unclear. In this paper, we isolated and characterized a temperature-conditional virescent mutant, OsV4, in rice （Oryza sativa cultivar Jiahual （WT, japonica rice variety））. The mutant displays albino phenotype and abnormal chloroplasts at the three leaf stage, which gradually turns green after the four leaf stage at a low temperature （20℃）. But the mutant always develops green leaves and well-developed chloroplasts at a high temperature （32℃）. Genetic and molecular analyses uncovered that OsV4 encodes a novel chloroplast-targeted PPR protein including four PPR motifs. Further investigations show that the mutant phenotype is associated with changes in chlorophyll content and chloroplast development. The OsV4 transcripts only accumulate to high levels in young leaves, indicating that its expression is tissue-specific. In addition, transcript levels of some ribosomal components and plastid- encoded polymerase-dependent genes are dramatically re- duced in the albino mutants grown at 20℃. These findings suggest that OsV4 plays an important role during early chloroplast development under cold stress in rice.
基金Supported by the State Key Basic Research and Development Plan of China （2004CB117203-2 and 2002CB111304）, the National Natural Science Foundation of China （30571176 and 30490250）, the Natural Science Foundation of Jiangsu Province （BK2004100） and the Program for Changjiang Scholars and Innovative Research Team in University （PCSIRT）.
文摘Soybean mosaic virus （SMV） is one of the most broadly distributed diseases worldwide. It causes severe yield loss and seed quality deficiency in soybean （Glycine max （L.） Merr.）. SMV Strain SC14 isolated from Shanxi Province, China, was a newly identified virulent strain and can infect Kefeng No. 1, a source with wide spectrum resistance. In the present study, soybean accessions, PI96983, Qihuang No. 1 and Qihuang No. 22 were identified to be resistant （R） and Nannong 1138-2, Pixianchadou susceptible （S） to SC14. Segregation analysis of PI96983 x Nannong 1138-2 indicated that a single dominant gene （designated as Rsc14） controlled the resistance to SC14 at both V2 and R1 developmental stages. The same results were obtained for the crosses of Qihuang No. 1 × Nannong 1138-2 and Qihuang No. 22 x Nannong 1138-2 as in PI96983 x×Nannong 1138-2 at V2 stage, but at R1 stage, the F1 performed as necrosis （a susceptible symptom other than mosaic）, F2 segregated in a ratio of 1R：2N：IS, and the progenies of necrotic （N） F2 individuals segregated also in R, N and S. It indicated that a single gene （designated as Rsc140, to be different from that of PI96983） controlled the resistance to SC14, its dominance was the same as in PI96983 × Nannong 1138-2 （without symptoms） at V2 stage and not the same at R1 stage. The tightly linked co-dominant simple sequence repeat （SSR） marker Satt334 indicated that all the heterozygous bands were completely corresponding to the necrotic F2 individuals, or all the necrotic F2 individuals were heterozygotes. It was inferred that necrosis might be due to the interaction among SMV strains, resistance genes, genetic background of the resistance genes, and plant development stage. Furthermore, the bulked segregant analysis （BSA） of SSR markers was conducted to map the resistance genes. In F2 of PI96983 × Nannong 1138-2, five SSR markers, Sat_297, Sat_234, Sat_154, Sct_033 and Sat_120, were found closely linked to Rsc14, with genetic distances of
