Integrated and comparative proteomics of high-oil and high-protein soybean seeds.

We analysed the global protein expression in seeds of a high-oil soybean cultivar (Jiyu 73, JY73) by proteomics. More than 700 protein spots were detected and 363 protein spots were successfully identified. Comparison of the protein profile of JY73 with that of a high-protein cultivar (Zhonghuang 13, ZH13) revealed 40 differentially expressed proteins, including oil synthesis, redox/stress, hydrolysis and storage-related proteins. All redox/stress proteins were less or not expressed in JY73, whereas the expression of the major storage proteins, nitrogen and carbon metabolism-related proteins was higher in ZH13. Biochemical analysis of JY73 revealed that it was in a low oxidation state, with a high content of polyunsaturated fatty acids and vitamin E. Vitamin E was more active than antioxidant enzymes and protected the soybean seed in a lower oxidation state. The characteristics of high oil and high protein in soybean, we revealed, might provide a reference for soybean nutrition and soybean breeding.

Movement of rhizobia inside tobacco and lifestyle alternation from endophytes to free-living rhizobia on leaves.

Rhizobia are well-known for their ability to infect and nodulate legume roots, forming a nitrogen-fixing symbiosis of agricultural importance. In addition, recent studies have shown that rhizobia can colonize roots and aerial plant tissues of rice as a model plant of the Graminaceae family. Here we show that rhizobia can invade tobacco, a model plant belonging to the Solanaceae family. Inoculation of seedling roots with five GFP-tagged rhizobial species followed by microscopy and viable plating analyses indicated their colonization of the surface and interior of the whole vegetative plant. Blockage of ascending epiphytic migration by coating the hypocotyls with Vaseline showed that the endophytic rhizobia can exit the leaf interior through stomata and colonize the external phyllosphere habitat. These studies indicate rhizobia can colonize both below and above-ground tissues of tobacco using a dynamic invasion process that involves both epiphytic and endophytic lifestyles.

[Differential diagnosis between intestinal stromal tumor and intestinal carcinoma by color doppler ultrasonography].

OBJECTIVE: To investigate the features of tumor appearance on transabdominal color doppler ultrasonography (CDUS) and its diagnostic value in the differential diagnosis between intestinal stromal tumor and intestinal carcinoma. METHODS: The preoperative features of the tumor mass on CDUS were reviewed retrospectively in 25 patients with intestinal stromal tumor and in 30 with intestinal carcinoma. All the cases were confirmed by surgery and pathological examination. RESULTS: Of the 25 cases with intestinal stromal tumor, 23 (92%) were found to be located in the small intestine and the majority presented as a hypoechoic solid mass with clear demarcation and rich color flow signals on CDUS, not growing around the intestinal cavity. A heterogeneous echogenic mass with anechoic space was shown in some stromal tumors. The CDUS showed that carcinoma were all in the colon or the rectum, and showed heterogeneous echoic solid masses with ill-defined margin, few color flow signals and pseudokidney sign was often observed in intestinal carcinoma because the mass grew around the intestinal cavity. Internal echo pattern, the relation between mass and intestinal cavity, and color doppler flow signal of intestinal stromal tumors were significantly different from those of intestinal carcinomas (all P<0.05). There were no statistical differences in lymphatic metastasis (P>0.05). CONCLUSION: CDUS is an effective method to differentiate intestinal stromal tumor from carcinoma.

Proteomic analysis of oil mobilization in seed germination and postgermination development of Jatropha curcas.

To understand oil mobilization in germinating seeds, we performed ultrastructural observation and proteomic analysis of endosperm in germinating Jatropha curcas seeds. Results showed that the oil mobilization was initiated during germination, and then the oil was consumed for early seedling development. The significant change in abundance of 50 protein spots during germination indicated that several pathways including beta-oxidation, glyoxylate cycle, glycolysis, citric acid cycle, gluconeogenesis, and pentose phosphate pathway were involved in the oil mobilization.