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Wei-Bo Yin

Publications and source records attributed to Wei-Bo Yin.

5 recordsLinked to original sources
PubMed2006

Chloroplast transformation.

In this chapter we briefly review the developmental history and current research status of chloroplast transformation and introduce the merits of chloroplast transformation as compared with the nuclear genome transformation. Furthermore, according to the chloroplast transformation achieved in oilseed rape (Brassica napus), we introduce the preparation of explants, transformation methods, system selection, identification methods of the transplastomic plants, and experimental results. The technical points, the bottleneck, and the further research directions of the chloroplast transformation are discussed in the notes.

Biological Assay↗
PubMed2005

Cloning of resistance gene analogs located on the alien chromosome in an addition line of wheat-Thinopyrum intermedium.

Homology-based gene/gene-analog cloning method has been extensively applied in isolation of RGAs (resistance gene analogs) in various plant species. However, serious interference of sequences on homoeologous chromosomes in polyploidy species usually occurred when cloning RGAs in a specific chromosome. In this research, the techniques of chromosome microdissection combined with homology-based cloning were used to clone RGAs from a specific chromosome of Wheat-Thinopyrum alien addition line TAi-27, which was derived from common wheat and Thinopyrum intermedium with a pair of chromosomes from Th. intermedium. The alien chromosomes carry genes for resistance to BYDV. The alien chromosome in TAi-27 was isolated by a glass needle and digested with proteinase K. The DNA of the alien chromosome was amplified by two rounds of Sau3A linker adaptor-mediated PCR. RGAs were amplified by PCR with the degenerated primers designed based on conserved domains of published resistance genes (R genes) by using the alien chromosome DNA, genomic DNA and cDNA of Th. intermedium, TAi-27 and 3B-2 (a parent of TAi-27) as templates. A total of seven RGAs were obtained and sequenced. Of which, a constitutively expressed single-copy NBS-LRR type RGA ACR 3 was amplified from the dissected alien chromosome of TAi-27, TcDR 2 and TcDR 3 were from cDNA of Th. intermedium, AcDR 3 was from cDNA of TAi-27, FcDR 2 was from cDNA of 3B-2, AR 2 was from genomic DNA of TAi-27 and TR 2 was from genomic DNA of Th. intermedium. Sequence homology analyses showed that the above RGAs were highly homologous with known resistance genes or resistance gene analogs and belonged to NBS-LRR type of R genes. ACR 3 was recovered by PCR from genomic DNA and cDNA of Th. intermedium and TAi-27, but not from 3B-2. Southern hybridization using the digested genomic DNA of Th. intermedium, TAi-27 and 3B-2 as the template and ACR 3 as the probe showed that there is only one copy of ACR 3 in the genome of Th. intermedium and TAi-27, but it is absent in 3B-2. The ACR 3 could be used as a specific probe of the R gene on the alien chromosome of TAi-27. Results of Northern hybridization suggested that ACR 3 was constitutively expressed in Th. intermedium and TAi-27, but not 3B-2, and expressed higher in leaves than in roots. This research demonstrated a new way to clone RGAs located on a specific chromosome. The information reported here should be useful to understand the resistance mechanism of, and to clone resistant genes from, the alien chromosome in TAi-27.

Amino Acid Sequence↗
PubMed2005

Influence of number of metastatic lymph nodes on survival of curative resected thoracic esophageal cancer patients and value of radiotherapy: report of 549 cases.

PURPOSE: To analyze the significance of the number of metastatic lymph nodes on survival with and without the addition of prophylactic postoperative radiotherapy (RT) after radical resection of thoracic esophageal carcinoma. METHODS AND MATERIALS: A total of 549 thoracic esophageal squamous cell cancer patients who had undergone radical resection were randomized by the envelope method into a surgery-alone group (S, n = 275) and a surgery plus RT group (S+R, n = 274). We performed a retrospective review of all patients according to the extent of metastasis. The patients were classified into three groups: Group 1, 269 patients (49.0%) without lymph node involvement; Group 2, 159 patients (29.0%) with one to two positive nodes; and Group 3, 121 patients (22.0%) with three or more positive lymph nodes. RESULTS: For the same T stage (T3), the 5-year survival rate for Groups 1, 2, and 3 was 50.6%, 29.3%, and 11.7%, respectively (p = 0.0000). For patients with Stage III, the 5-year survival rate for Groups 1 (T4N0M0), 2 (T3-T4N1M0), and 3 (T3-T4N2M0) was 58.1%, 30.6%, and 14.4%, respectively (p = 0.0092). The 5-year survival rate of the S and S+R groups with positive lymph nodes (Groups 2 and 3) was 17.6% and 34.1% (p = 0.0378). In the positive lymph node groups, the incidence of failure by intrathoracic lymph node metastasis and supraclavicular lymph node metastasis in the S+R group (21.5% and 4.6%, respectively) was lower than in the S group (35.9% and 19.7%, respectively; p <0.012). In the negative lymph node group, the incidence of failure by intrathoracic lymph node metastasis in the S and S+R groups was 27.8% and 13.3%, respectively (p = 0.006). Hematogenous metastasis was the greatest (27.5%) in Group 3 (three or more positive lymph nodes). CONCLUSION: The number of metastatic lymph nodes is one of the important factors affecting the survival of patients with thoracic esophageal carcinoma. In our study, postoperative RT improved the survival of patients with positive lymph nodes. Additionally, postoperative RT reduced the incidence of intrathoracic recurrence and supraclavicular lymph node metastasis for all patients.

Adult↗
PubMed2004

Screening and analysis of differentially expressed genes from an alien addition line of wheat Thinopyrum intermedium induced by barley yellow dwarf virus infection.

The alien addition line TAI-27 contains a pair of chromosomes of Thinopyrum intermedium that carry resistance against barley yellow dwarf virus (BYDV). A subtractive library was constructed using the leaves of TAI-27, which were infected by Schizaphis graminum carrying the GAV strain of BYDV, and the control at the three-leaf stage. Nine differentially expressed genes were identified from 100 randomly picked clones and sequenced. Two of the nine clones were highly homologous with known genes. Of the remaining seven cDNA clones, five clones matched with known expressed sequence tag (EST) sequences from wheat and (or) barley whereas the other two clones were unknown. Five of the nine differentially expressed sequences (WTJ9, WTJ11, WTJ15, WTJ19, and WTJ32) were highly homologous (identities >94%) with ESTs from wheat or barley challenged with pathogens. These five sequences and another one (WTJ18) were also highly homologous (identities >86%) with abiotic stress induced ESTs in wheat or barley. Reverse Northern hybridization showed that seven of the nine differentially expressed cDNA sequences hybridized with cDNA of T. intermedium infected by BYDV. Three of these also hybridized with cDNA of line 3B-2 (a parent of TAI-27) infected by BYDV. The alien chromosome in TAI-27 was microdissected. The second round linker adaptor mediated PCR products of the alien chromosomal DNA were labeled with digoxygenin and used as the probe to hybridize with the nine differentially expressed genes. The analysis showed that seven differentially expressed genes were homologous with the alien chromosome of TAI-27. These seven differentially expressed sequences could be used as ESTs of the alien chromosome of TAI-27. This research laid the foundation for screening and cloning of new specific functional genes conferring resistance to BYDV and probably other pathogens.

Blotting, Northern↗