Ptac启动子等相关知识（Ptac promoter and other related knowledge）.doc

Ptac启动子等相关知识（Ptac promoter and other related knowledge） The first chapter ─ 1. Nuclease: the RNA that has catalytic activity is named as ribozyme, which is also referred to as enzyme RNA. The enzyme RNA is not used for Rnase, the former is RNA, the latter is protein. The nuclease is hammerhead 2. What is antisense RNA? What is its function and medical significance? To combine with specific mRNA complementary RNA, it widely involved in virus and cytology many important life process adjustment, can block the mRNA translation, can selectively shut down genes, one in DNA replication and transcription plays an important regulatory role, promote le with artificial antisense nucleic acids regulate gene expression Howard technology development. Its function: block mRNA translation and inhibit DNA replication to selectively shut down genes. Significance: participating in gene regulation can be used for gene therapy 3. Try to describe the formation of three strands of DNA, biological significance and application value. Due to the double helix ─ shares after slight rotation, folding, the stock of one base to one base are connected by Hoogsteen hydrogen bond like TAT the double helix, CGC, TAA, CGG. (pictured), three chain DNA structure types and meaning: (1) can be used as precise cutting one molecular scissors one target DNA sequences (transcription), (2) the inhibition of gene expression (antisense DNA gene therapy) (3) influence DNA and protein and DNA replication, transcription, etc, in addition, there are four strands of DNA. 5. What is RNAi? What is the mechanism and application prospect? The small molecules double-stranded RNA can trigger post-transcriptional gene silencing or RNA interference (RNAi). The dsRNA can be degraded by Dicer enzyme, and then the gene interference (or silence), which is to block the expression of le gene. (mechanism diagram) Features: (1) different SiRNA sequences can exercise the specific identification, cutting action (2) mRNA was cut up dsR