Objective： To investigate the impact of beta-elemene injection on the growth and alpha-tubule of human hepatocarcinoma HepG2 cells. Methods： Cell proliferation was assessed by MTT assay. Cell cycle distribution was ...Objective： To investigate the impact of beta-elemene injection on the growth and alpha-tubule of human hepatocarcinoma HepG2 cells. Methods： Cell proliferation was assessed by MTT assay. Cell cycle distribution was detected by flow cytometry （FCM）. The mRNA expression of alpha-tubulin was measured by RT-PCR. Western blot analysis was used to determine protein expression of alpha-tubulin and the polymerization of tubulin. Results： Beta-elemene injection inhibited HepG2 cells proliferation in a dose- and time-dependent manner; FCM analysis indicated beta-elemene injection induced cell cycle arrested at S phase. RT-PCR and western- blot analysis showed that beta-elemene injection down-regulated alpha-tublin at both mRNA and protein levels, presenting a dose-dependent manner. Moreover, beta-elemene injection reduced the polymerization of microtubules in a dose-dependent manner. Conclusions： Beta-elemene injection can inhibit the proliferation of hepatoma HepG2 cells and induce cell apoptosis, the mechanism might be partly related to the down-regulation of alpha-tubulin and inhibition of microtubular polymerization.展开更多
The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent...The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent classification is still lacking and several important questions about the phylogenetic relationships within this group remain unsolved. To improve our understanding of these relationships, we constructed phylogenetic trees using the nucleotide sequences of the small-subunit rRNA (SSrRNA) gene and amino acid sequences of actin I and α-tubulin. Analyses of SSrRNA gene sequences indicated that: 1) the Sporadotrichida sensu Lynn (2008) and the Oxytrichidae are polyphyletic; 2) the Uroleptus species, which are classified to urostylids, formed a sister group with the oxytrichids; 3) Halteria grandinella, which is grouped morphologically with oligotrich species, clustered within the oxytrichids. These results are congruent with previous studies based on SSrRNA gene sequences. However, the amino acid sequences of actin I and α-tubulin yielded different topologies. The main results are: 1) in all phylogenetic trees, the genus Oxytricha was paraphyletic; 2) Uroleptus was sister to a subset of Urostyla and Holosticha, albeit with low supporting values; 3) Halteria grandinella was separated distantly from the Oxytrichidae in trees inferred from actin I amino acid sequences but clustered with oligotrichids in the α-tubulin analysis. The inconsistency among the trees inferred from these different molecular markers may be caused by rapidly accumulated genetic characterizations of ciliates. Further studies with additional molecular markers and sampling of more taxa are expected to better address the relationships among sporadotrichids.展开更多
We describe the formation of the major axon pathways in the embryonic central and peripheral nervous systems of the amphipod crustacean Orchestia cavimana Heller,1865 by means of antibody staining against acetylated a...We describe the formation of the major axon pathways in the embryonic central and peripheral nervous systems of the amphipod crustacean Orchestia cavimana Heller,1865 by means of antibody staining against acetylated alphatubulin.The data add to a long list of previous studies of various other aspects of development in Orchestia and provide a basis for future studies of neurogenesis on a deeper cellular and molecular level.Orchestia exhibits a tripartite dorsal brain,which is a characteristic feature of euarthropods.Its anlagen are the first detectable structures in the developing nervous system and can be traced back to distinct neuronal cell clusters in the early embryo.The development of the ventral nervous system proceeds with an anteroposterior gradient of development.In each trunk segment,the longitudinal connectives and the anterior commissure form first,followed by the intersegmental nerve,the posterior commissure and segmental nerves,respectively.A single commissure of a vestigial seventh pleonal segment is found.In the peripheral nervous system we observe a spatial and temporal pattern of leg innervation,which is strikingly similar in both limb types,the uniramous pereopods and the biramous pleopods.A proximal leg nerve splitting distally into two separated nerves probably reflects a general feature of crustaceans.展开更多
基金The General Program of National Natural Science Foundation of China:Research Fund for the mechanism of Arenobufagin space isomer inhibits lymphatic metastasis of mouse hepatocarcinomaThe Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education MinistrySpecialized Research Fund for the Doctoral Program of Higher Education(NO.20102105120002)
文摘Objective： To investigate the impact of beta-elemene injection on the growth and alpha-tubule of human hepatocarcinoma HepG2 cells. Methods： Cell proliferation was assessed by MTT assay. Cell cycle distribution was detected by flow cytometry （FCM）. The mRNA expression of alpha-tubulin was measured by RT-PCR. Western blot analysis was used to determine protein expression of alpha-tubulin and the polymerization of tubulin. Results： Beta-elemene injection inhibited HepG2 cells proliferation in a dose- and time-dependent manner; FCM analysis indicated beta-elemene injection induced cell cycle arrested at S phase. RT-PCR and western- blot analysis showed that beta-elemene injection down-regulated alpha-tublin at both mRNA and protein levels, presenting a dose-dependent manner. Moreover, beta-elemene injection reduced the polymerization of microtubules in a dose-dependent manner. Conclusions： Beta-elemene injection can inhibit the proliferation of hepatoma HepG2 cells and induce cell apoptosis, the mechanism might be partly related to the down-regulation of alpha-tubulin and inhibition of microtubular polymerization.
基金Supported by the National Natural Science Foundation of China (No. 30870264, 40976075)a grant from the Center of Excellence in Biodiversity, King Saud Universitya Marie Curie Incoming International Fellowship within the 7th European Community Framework Programme
文摘The sporadotrichid ciliates are an especially diverse group. A number of investigators have studied the morphological, morphogenetic, and molecular relationships among members of this group. Despite this, a consistent classification is still lacking and several important questions about the phylogenetic relationships within this group remain unsolved. To improve our understanding of these relationships, we constructed phylogenetic trees using the nucleotide sequences of the small-subunit rRNA (SSrRNA) gene and amino acid sequences of actin I and α-tubulin. Analyses of SSrRNA gene sequences indicated that: 1) the Sporadotrichida sensu Lynn (2008) and the Oxytrichidae are polyphyletic; 2) the Uroleptus species, which are classified to urostylids, formed a sister group with the oxytrichids; 3) Halteria grandinella, which is grouped morphologically with oligotrich species, clustered within the oxytrichids. These results are congruent with previous studies based on SSrRNA gene sequences. However, the amino acid sequences of actin I and α-tubulin yielded different topologies. The main results are: 1) in all phylogenetic trees, the genus Oxytricha was paraphyletic; 2) Uroleptus was sister to a subset of Urostyla and Holosticha, albeit with low supporting values; 3) Halteria grandinella was separated distantly from the Oxytrichidae in trees inferred from actin I amino acid sequences but clustered with oligotrichids in the α-tubulin analysis. The inconsistency among the trees inferred from these different molecular markers may be caused by rapidly accumulated genetic characterizations of ciliates. Further studies with additional molecular markers and sampling of more taxa are expected to better address the relationships among sporadotrichids.
基金We thank the plant physiology section at Humboldt University,Berlin for help with the CLSM.We are very grateful to Caterina Biffis,Georg Brenneis and the 2 anonymous reviewers for the helpful advice.We also thank Stephen Rossiter for improving the English.
文摘We describe the formation of the major axon pathways in the embryonic central and peripheral nervous systems of the amphipod crustacean Orchestia cavimana Heller,1865 by means of antibody staining against acetylated alphatubulin.The data add to a long list of previous studies of various other aspects of development in Orchestia and provide a basis for future studies of neurogenesis on a deeper cellular and molecular level.Orchestia exhibits a tripartite dorsal brain,which is a characteristic feature of euarthropods.Its anlagen are the first detectable structures in the developing nervous system and can be traced back to distinct neuronal cell clusters in the early embryo.The development of the ventral nervous system proceeds with an anteroposterior gradient of development.In each trunk segment,the longitudinal connectives and the anterior commissure form first,followed by the intersegmental nerve,the posterior commissure and segmental nerves,respectively.A single commissure of a vestigial seventh pleonal segment is found.In the peripheral nervous system we observe a spatial and temporal pattern of leg innervation,which is strikingly similar in both limb types,the uniramous pereopods and the biramous pleopods.A proximal leg nerve splitting distally into two separated nerves probably reflects a general feature of crustaceans.
