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I have been studying biological sciences for several years. In college, I majored in
biochemistry and in graduate school, developmental biology. I am educated to be a molecular biologist and my
interest is to handle problems in the field such as neural science and developmental
biology which have become feasible to solve only recently in the advent of molecular
biology.
In college, I spent the first 2 years mostly studying general courses such as chemistry, math and physics. In the next two years I study courses related to my major and worked on my bachelor's thesis. I went to the lab lead by Prof Quanbao Gu in Chinese Academy of Science Shanghai Institute of Cell Biology to finish the thesis in the fourth college year. My work there is to co-express NMDA receptor and Glycine transporter into amphibian oocytes and then do some electro physiological assays. Our aim is testing whether the co expression of these two transmembrane proteins which is found uniquely in the hippopotamus region is related to Long Term Potentiation which is though to happen in this region in the brain. It is reported that glycine in the cleft of synapse can enhance the NMDA effect on its receptor. The activation of NMDA receptor will cause Calcium influx. Meanwhile, the raise of intracellular Calcium level can cause the outflux of glycine through glycine transproter. So it is at least theoretically possible the these two protein can make a positive feedback circuit in the synapse region. However, in our experiment we can not totally mimic the environment of the synapse since we can not contain the extracellular space to the extent like that in synapses. Meanwhile only a small portion of the expressed transmembrane proteins can properly assmemble on the membrane. For these reasons, we have not detect LTP in our expriments. However, I still got enough experiment training and data to finish my thesis. In the graduate period, I worked in the group of early embryogenesis led by Prof. Xiaoyan Ding. We use Xenopus laevis embryo to research its pattern formation. I have take part in a work assaying the effect of Wnt-1 on the establishing of the dorsal-ventral axis. My part work is expressing a His-tagged Wnt-1 peptide in E. Coli and prepare antibody using this as antigen. I finally got a high sensitive multi-clonal antisera. By immuno-histochemical assay on embryo sections, the reaction region is in accordance with the reported wnt expressing region. . I found in my experiment that Ni2+ can induce the formation of cement gland tissue in ectoderm explants from blastula stage embryos. The default fate of the ectoderm explant from this stage embryos is epidermis tissue, however it also has the potential to become neural tissues. This can be induced by neural inducing factors such as chordin and noggin. Some part of the induced ectoderm explant also become cement gland. In my experiment I found Ni2+ can induce the entire ectoderm explant into cement gland. As Ni2+ is a T-type calcium channel blocker, I tested whether another T-type calcium channel blocker Amiloride and N-type calcium channel blocker Nifedipine have similar effects. I found while Nifedipine totally has not inducing effect, Amiloride did induce a portion of the explants into cement gland the not as efficient as Ni2+. Our preliminary expriments show that this effect may be related with FGF signalling pathway. I am currently taking part in the work assaying transcriptional regulation of dorsal-vental axis pattern formation genes such as noggin. By screen a Xenopus laevis genomic sequence library, we have got the clone carrying 4kb of the upstream regulation sequence. We have sequenced it and made mutations. By adding luciferase and lacZ downstream of this regulation region, we are testing the effect of the mutation on the level and position of expression. We want to find key regulation units. This work is still under way. |