Ti Plasmid contd…

The Ti plasmid contains genes for auxin and cytokinin formation, and for synthesis or utilization of opines. Ti plasmids range in size from 200 to 800 kbp. Of this, about 30% is common to nopaline and octopine plasmids (Genes VIII, Benjamin Lewin, pp. 525). The genes of common region are required for the interaction between [...]

Read Full Post »

Ti Plasmid

Ti plasmids are divided into 4 groups depending upon the types of opines that are synthesized.
1) Nopaline plasmids: These carry genes for synthesis of nopaline in tumors and for utilizing it in bacteria. The tumors carrying nopaline plasmids can differentiate into shoots with abnormal structures. They are called teratomas as they are analogous to certain [...]

Read Full Post »

Agrobacterium tumefaciens

Agrobacterium tumefaciens, a soil-borne bacterium, causes the crown gall disease in most dicots. The disease leads to the formation of tumor on the site of infection. The tumor-induction is dependent upon the bacterium’s ability to transfer its DNA to the plant cell: The bacterium attaches itself to the host plant cell and transfers part of [...]

Read Full Post »

miRNA and siRNA

Both microRNAs (miRNA) and small interfering RNAs (siRNA) play integral roles in the RNAi. Both these molecules play similar roles but differ in their origin . siRNAs are derived from the cleavage of long dsRNA precursors, which could either be produced endogenously or introduced into the cell from outside. When produced endogenously, siRNAs are derived [...]

Read Full Post »

RISC: RNA-induced Silencing Complex

During the course of gene silencing by RNAi the destruction of target mRNA is catalysed by the siRNA-guided, RNA-induced silencing complex (RISC). RISC, composed of two signature components (siRNA/miRNA and Argonaute), is an endonuclease , which catalyses the cleavage of a single phosphodiester bond on the RNA target. The cleavage reaction requires “Mg2+, but not [...]

Read Full Post »

RNAi: Regulating Gene Expression by RNA

RNA interference (RNAi) has emerged as one of the significant mechanisms playing a major role in gene expression regulation. The mechanism relies on diverse small noncoding RNAs, the prominent being siRNAs (small interfering RNAs) and miRNAs (microRNAs), for efficient gene silencing. The RNAi pathway is started by the enzyme Dicer, which is a ribonuclease [...]

Read Full Post »

A brief introduction

A desire to pen down, or key in, important happenings on diverse aspects, issues, sites, links, tutorials, protocols, research papers, journals, companies, and all things molecular biology and biotechnology gave birth to this blog.

Read Full Post »