Ubiquitinome Profiling Reveals the Landscape of Ubiquitination Regulation in Rice Young Panicles / 基因组蛋白质组与生物信息学报·英文版

Ubiquitination, an essential post-transcriptional modification (PTM), plays a vital role in nearly every biological process, including development and growth. Despite its functions in plant reproductive development, its targets in rice panicles remain unclear. In this study, we used proteome-wide profiling of lysine ubiquitination in rice (O. sativa ssp. indica) young panicles. We created the largest ubiquitinome dataset in rice to date, identifying 1638 lysine ubiquitination sites on 916 unique proteins. We detected three conserved ubiquitination motifs, noting that acidic glutamic acid (E) and aspartic acid (D) were most frequently present around ubiquitinated lysine. Enrichment analysis of Gene Ontology (GO) annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of these ubiquitinated proteins revealed that ubiquitination plays an important role in fundamental cellular processes in rice young panicles. Interestingly, enrichment analysis of protein domains indicated that ubiquitination was enriched on a variety of receptor-like kinases and cytoplasmic tyrosine and serine-threonine kinases. Furthermore, we analyzed the crosstalk between ubiquitination, acetylation, and succinylation, and constructed a potential protein interaction network within our rice ubiquitinome. Moreover, we identified ubiquitinated proteins related to pollen and grain development, indicating that ubiquitination may play a critical role in the physiological functions in young panicles. Taken together, we reported the most comprehensive lysine ubiquitinome in rice so far, and used it to reveal the functional role of lysine ubiquitination in rice young panicles.

Inhibitory effect of ganciclovir on proliferation of cord blood hematopoietic progenitor cells after infection of human cytomegalovirus in vitro / 中国组织工程研究

BACKGROUND: Clinically, in patients undergoing hematopoietic stem cell transplantation (HSCT), human cytomegalovirus (HCMV) can be associated with delayed platelet engraftment, phenotypically abnormal peripheral blood leukocytes, and graft rejection, possibly through a direct viral effect on hematopoietic progenitor cells after HCMV infection. OBJECTIVE: To investigate the inhibitory effect of ganciclovir (GCV) on proliferation of colony forming unit (CFU) granulocyte-macrophage (CFU-GM), CFU-erythroid (CFU-E), CFU T-lymphocyte (CFU-TL), CFU-multipotential (CFU-Mix) and CFU-megakaryocyte (CFU-Mk) progenitor cells of cord blood (CB) and the protective effects on them. DESIGN: Contrast observational study.SETTING: Department of Molecular Biology, Affiliated Hospital of Luzhou Medical College.PARTICIPANTS: A total of 20 cord blood (CB) samples (with 10 mL for each sample) from fetal umbilical vein of normal term spontaneous delivery neonates were provided by the Department of Gynaecology and Obstetrics, Affiliated Hospital of Luzhou Medical College. All the patients were informed and agreed with the experiment.METHODS: The experiment was carried out in the Department of Molecular Biology, Affiliated Hospital of Luzhou Medical College from June 2004 to December 2006. Colony forming unit-assay was applied to observe the suppression effect of HCMV-AD169 strain on CFU-GM, CFU-E, CFU-TL, CFU-Mix and CFU-Mk of CB with the presence of GCV. The techniques of polymerase chain reaction (PCR) and fluorescence quantification PCR were used to demonstrate the existence of HCMV-AD169 DNA in the colony cells of cultured CFU-GM, CFU-E, CFU-TL, CFU-Mix and CFU-Mk. Normal progenitor cells culture system was regarded as blank control group; normal progenitor cells culture system with inactivated HCMV fluid as inactivated (IV) control group.MAIN OUTCOME MEASURES: ① The number and maintaining duration of colonies of cultured progenitor cells were counted by using a light inverted phase contrast microscope. ② The techniques of PCR and fluorescence quantification PCR were used to demonstrate the existence of HCMV-AD169 DNA in the colony cells of cultured progenitor cells.RESULTS: ① Number and lasting time of colonies: The numbers of CFU-GM, CFU-E, CFU-TL, CFU-Mix and CFU-Mk colonies in the HCMV infection group were significantly less than those in the blank control group (P < 0.01). The maintaining duration of colonies in the HCMV infection group was significantly shorter than that in the blank control group (P < 0.01). HCMV-DNA copies of colony cells of GCV group decreased significantly by using fluorescence quantification PCR compared with HCMV group (P < 0.01), while negative in blank control and inactivated control in CFU-MK and CFU-Mix. ② CFU Growth rate: The Growth rate of colonies was 37.4%, 74.2%, 40.1%, 67.4% and 38.9% of CFU-GM, CFU-E, CFU-TL, CFU-Mix and FU-MK, respectively. ③ CFU-HCMV-AD169 DNA: Fluorescence quantification PCR showed that nucleonic acid content of progenitor cells after GCV-affected HCMV infection was decreased as compared with that after HCMV infection (P < 0.01).CONCLUSION: The differentiation and proliferation of CFU-GM, CFU-E, CFU-TL, CFU-Mix and CFU-Mk are significantly inhibited after infected with CMV-AD169 strain. The growth of hematopoietic progenitor cell after HCMV-AD169 infection is promoted by GCV, which suggests that GCV has an effect of anti-HCMV in vitro.