95Capricornus的个人资料

发一份我写的作业，嗯，参考免疫八的。关于BCR形成的一份作业。 The immunoglobulin bound to the B lymphocytes is the receptor of theB lymphocyte (BCR). It is also an existing form of the antibody, so the BCRhave the light chain and the heavy chain. What is the machinery of the formation of the antibody? It is due tothe rearrangement of the gene. There are two types of chains in the antibody,and the formation of each other is different. In the formation of the lightchain, V gene segment (variable, V) and J gene segment (Joining, J) first jointogether, becoming the V-J. Then the V-region (V-J) is close to the C-region,but there is also a short intron between the V and C. After transcription,under the RNA splicing, the mRNA get rid of the intron between V and L (leadersegment, which can direct the protein into the cell’s secretory pathways), andthe intron between V and C, and the mRNA can be translated. As for the heavychain, there is a diversity segment (D) between the V and J. The D and J joinstogether first, then it is similar to the formation of the light chain. But,what is different is that the C-region has a lot of exons, between each exonthere is an intron, and one of the exons can become a hinge region after ittranslated, for it can form the disulfide bonds. How can the DNA rearrangement be regulated? There is a RSS(Recombination signal sequence) adjacent to the functional segment. RSSincludes three parts, a heptamer (conversed,-5’CACAGTG3’-), a spacer (either 12or 23 base pairs) and a nonamer (conversed,-5’ACAAAAACC3’-). With the 12/23rule, the V and J(or V, D and J can join to each other orderly). When the joining segments are in the same orientation, the signaljoint is in a circular piece of extrachromosomal DNA, which is lost from thegenome when the cell divides. While in the opposite orientation, alignment ofthe RSSs requires the coiled topology, rather than a simple loop like theformer, so that joining the ends of the two heptamer sequences results in theinversion and integration of intervening DNA into a new position on thechromosome. Again, the joining of the V and J segments creates a functionalV-region exon. Thereare lots of enzymes play roles in the joining, like RAG1/2, Ku70/80 etc. Normal 0 7.8 磅 0 2 false false false EN-US ZH-CN X-NONE /* Style Definitions */ table.MsoNormalTable{mso-style-name:普通表格;mso-tstyle-rowband-size:0;mso-tstyle-colband-size:0;mso-style-noshow:yes;mso-style-priority:99;mso-style-parent:"";mso-padding-alt:0cm 5.4pt 0cm 5.4pt;mso-para-margin:0cm;mso-para-margin-bottom:.0001pt;mso-pagination:widow-orphan;font-size:10.5pt;mso-bidi-font-size:11.0pt;font-family:"Calibri","sans-serif";mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-font-kerning:1.0pt;}

细胞被感染了…… 培养的细胞被感染了，还要重新弄……额，有没有细胞培养的经验呢?

我竟然成为生命科学吧小吧了！！哈哈，成为小吧了，平时不怎么上贴吧的，这回要多来了，对生命科学感兴趣的同学欢迎来哦~~

我竟然成为小吧了！！没想到我竟然成为小吧了，看来要多上贴吧看看了。

求指点测细胞内氨基酸浓度的方法我想测量大肠杆菌内多种游离氨基酸浓度或氨基酸酰tRNA的浓度，应该怎么测呢？求指点~~