Promoter-associated RNAs and promoter-targeted RNAs.

The world of RNAs is much more complex than previously thought, and has rapidly emerged as one of the most actively researched topics in the life sciences. Recently, two findings in this field were reported and given special attention: promoter-associated RNAs (paRNAs), a novel class of RNAs with numerous potential functions; and promoter-targeted RNA-induced transcriptional gene regulation, a new regulatory mechanism to control transcription. In this review, we summarize the studies in these two areas, and outline the current understanding with respect to the potential biological functions of paRNAs, and the molecular mechanisms of promoter-targeted RNA-induced transcriptional gene silencing and activation. Additionally, we seek to integrate these two areas, as paRNAs may have potential biological links with promoter-targeted RNA-induced transcriptional gene regulation. Finally, we will discuss the significance of identifying paRNAs and the possible use of promoter-targeted RNAs in gene regulation and therapy.

[Single nucleotide polymorphism analysis in chicken insulin-like growth factor-II gene and its associations with growth and carcass traits].

In this experiment, F2 chicken derived from Broilers crossing with Silky was used to study the effect of insulin-like growth factor-II gene on growth and carcass traits. The partial gene was amplified by two pairs of primers, and single nucleotide polymorphism (SNPs) was detected by the technique of restriction fragment length polymorphism (RFLP), and then confirmed by DNA sequencing. The mutation was found in the exon-2 of the gene, and can be clarified by cutting of restriction enzyme Aci-I. The result of least square analysis showed the gene was significantly related with growth and carcass traits. It implied that the insulin-like growth factor-II gene could be a genetic locus or linked to a major gene affecting greatly the growth and carcass traits in chicken.

[The true recognizing sequence of the restriction enzyme whose recognizing sequence is nonpalindromic].

The recognizing sequence of restriction enzyme includes palindrome and nonpalindromic, and DNA is double helix complementary strands. So the recognizing sequences of palindrome enzyme in two strands of DNA were identical,and can be considered of one sequence. But for nonpalindromic restriction enzyme,the recognizing sequences of two strands of DNA were not identical. Therefore the true recognizing sequences are not only one. In this experiment,an enzyme cleavage reaction was carried out which confirmed that the true recognizing sites/sequences of nonpalindromic enzyme are two instead of one.