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Chen Xu Bing Wang Hailu Heng Jiangmei Huang Cuihong Wan 《Molecular & cellular proteomics : MCP》2022,21(4):100224
The filamentous cyanobacterium Anabaena sp. PCC 7120 can differentiate into heterocysts to fix atmospheric nitrogen. During cell differentiation, cellular morphology and gene expression undergo a series of significant changes. To uncover the mechanisms responsible for these alterations, we built protein–protein interaction (PPI) networks for these two cell types by cofractionation coupled with mass spectrometry. We predicted 280 and 215 protein complexes, with 6322 and 2791 high-confidence PPIs in vegetative cells and heterocysts, respectively. Most of the proteins in both types of cells presented similar elution profiles, whereas the elution peaks of 438 proteins showed significant changes. We observed that some well-known complexes recruited new members in heterocysts, such as ribosomes, diflavin flavoprotein, and cytochrome c oxidase. Photosynthetic complexes, including photosystem I, photosystem II, and phycobilisome, remained in both vegetative cells and heterocysts for electron transfer and energy generation. Besides that, PPI data also reveal new functions of proteins. For example, the hypothetical protein Alr4359 was found to interact with FraH and Alr4119 in heterocysts and was located on heterocyst poles, thereby influencing the diazotrophic growth of filaments. The overexpression of Alr4359 suspended heterocyst formation and altered the pigment composition and filament length. This work demonstrates the differences in protein assemblies and provides insight into physiological regulation during cell differentiation. 相似文献
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Mária Chrenková A. Sommer Zuzana Čerešňáková Soňa Nitrayová Miroslava Prostredná 《Archives of animal nutrition》2013,67(3):229-235
The aim of this study was to determine the composition and nutritional value of conventional and transgenic, so-called Roundup Ready (RR) maize with an introduced gene of glyphosate resistance. Crude protein, crude fibre, ash, fat, starch, sugar, amino acids, fatty acid and macroelement levels were determined by chemical analysis. In both maize lines a low level of Ca (0.15g.kg m 1 DM) and of the essential amino acids lysine and tryptophan (2.6 and 1.7g.kgm 1 DM, respectively) were observed. In the biological experiment carried out on rats the tested maize lines were the only dietary sources of nitrogen, thus, the experimental diets contained 9% CP in dietary dry matter. In the feeding experiment no significant differences in the protein efficiency ratio (PER) were observed between groups receiving conventional or transgenic maize (1.51 and 1.41, respectively). Also almost equal results were obtained in the balance experiments. Both maize lines revealed a high nitrogen digestibility (84.9 and 84.5%, respectively) and the net protein utilization amounted to 63.5 and 63.2%, respectively. From these results can be concluded that regarding nutrient composition and utilisation, genetically modified (RR) maize is equivalent to isogenic maize. 相似文献
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The annexins are a multifamily of calcium-regulated phospholipid-binding proteins. To investigate the roles of annexins in fiber development, four genes encoding putative annexin proteins were isolated... 相似文献
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Melissa Carrillo Suraj Pandey Juan Sanchez Moraima Noda Ishwor Poudyal Luis Aldama Tek Narsingh Malla Elin Claesson Weixiao Yuan Wahlgren Denisse Feliz Vukica Šrajer Michał Maj Leticia Castillon So Iwata Eriko Nango Rie Tanaka Tomoyuki Tanaka Luo Fangjia Marius Schmidt 《Structure (London, England : 1993)》2021,29(7):743-754.e4
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Haijing Fu Rui Chen Yue Wang Yang Xu Chun Xia Bing Zhang 《Journal of cellular and molecular medicine》2021,25(24):11198-11211
Reticulocalbin1 (RCN1) is implicated in tumorigenesis and tumour progression. However, whether RCN1-mediated bone metastasis of non-small cell lung cancer (NSCLC) cells was elusive. Here, we assessed the effect of osteoblast-conditioned medium (CM) on proliferation and migration of NSCLC cell line, NCI-H1299 and NCI-H460 cells, and identified the soluble mediators in CMs from osteoblasts and NSCLC cells using MTT, Clonogenicity, Transwell, wound healing, RT-PCR, and Western blotting assays, and LC-MS/MS analysis, respectively. Furthermore, the role of RCN1 was investigated in NSCLC cells cultured with or without osteoblast-CM. Tumour growth and bone resorption were measured in a nude mouse model bearing NCI-H1299 cells transduced with shRNA/RCN1 vector using in vivo imaging technique and micro-CT. The results showed that RCN1 with a higher abundance in osteoblast-CM, which was present in extracellular vesicles (EVs), enhanced RCN1 expression in NSCLC cells. Osteoblast-CM partially offset the inhibitory effect of RCN1 depletion on proliferation and migration of NSCLC cells. RCN1 depletion-induced endoplasmic reticulum (ER) stress caused by increasing GRP78, CHOP, IRE1α, p-IRE1α, p-PERK and p-JNK, which was positively regulated by self-induced autophagy, contributed to suppression of proliferation and migration in NCI-H1299 cells. Therefore, osteoblasts produced RCN1 to transfer into NSCLC cells partially through EVs, facilitating proliferation and migration of NSCLC cells via blocking ER stress. RCN1 could be required for proliferation and migration of NSCLC cells regulated by osteoblast-CM. 相似文献