What Is RNA Silencing In Plants?

What information does RNA contain?

RNA is very similar to DNA, but differs in a few important structural details: RNA is single stranded, while DNA is double stranded.

Also, RNA nucleotides contain ribose sugars while DNA contains deoxyribose and RNA uses predominantly uracil instead of thymine present in DNA..

What controls gene expression?

Gene expression is primarily controlled at the level of transcription, largely as a result of binding of proteins to specific sites on DNA. … The regulator gene codes for synthesis of a repressor molecule that binds to the operator and blocks RNA polymerase from transcribing the structural genes.

What is RNA in plants?

Plant small RNAs are 21–24-nucleotide non-coding RNA molecules that are involved in RNA silencing. 16. In plants, RNA silencing plays a role in the maintenance of heterochromatin and in antiviral defense. 17. Plant small RNAs can be divided into two main classes: microRNAs (miRNAs) and small interfering RNAs (siRNAs).

Which RNA can induce gene silencing?

1. RNA SILENCING PATHWAYS IN PLANTS. RNA silencing is an evolutionarily conserved mechanism in eukaryotes. It is induced by double-stranded RNA (dsRNA) or hairpin structured RNA (hpRNA), involving common factors including Dicer or Dicer-like (DCL) and Argonaute (AGO) family proteins [1-3].

What is the difference between siRNA and miRNA?

The siRNA is an exogeneous double-stranded RNA uptaken by the cell, generally, are viral RNAs, it is also encoded by heterochromatin regions and transposons. Whereas the miRNA are endogenous single-stranded, non-coding RNA molecule, by forming a hairpin structure, it becomes duplex.

How does RNA defend against viruses?

RNAi not only protects against viruses by degrading viral RNA, but hosts and viruses can also use RNAi to manipulate each other’s gene expression, and hosts can encode microRNAs that target viral sequences. In response, viruses have evolved a myriad of adaptations to suppress and evade RNAi.

What is the function of microRNA?

A microRNA (abbreviated miRNA) is a small non-coding RNA molecule (containing about 22 nucleotides) found in plants, animals and some viruses, that functions in RNA silencing and post-transcriptional regulation of gene expression. miRNAs function via base-pairing with complementary sequences within mRNA molecules.

What is the difference between DNA and RNA?

Like DNA, RNA is made up of nucleotides. … There are two differences that distinguish DNA from RNA: (a) RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine.

How does the lac operon work?

Structure of the lac operon Genes in the lac operon specify proteins that help the cell utilize lactose. lacZ encodes an enzyme that splits lactose into monosaccharides (single-unit sugars) that can be fed into glycolysis. Similarly, lacY encodes a membrane-embedded transporter that helps bring lactose into the cell.

What is gene silencing in plants?

Gene silencing is the regulation of gene expression in a cell to prevent the expression of a certain gene. … When genes are silenced, their expression is reduced. In contrast, when genes are knocked out, they are completely erased from the organism’s genome and, thus, have no expression.

What is RNA interference and how does it work?

The term RNA interference (RNAi) was coined to describe a cellular mechanism that use the gene’s own DNA sequence of gene to turn it off, a process that researchers call silencing. In a wide variety of organisms, including animals, plants, and fungi, RNAi is triggered by double-stranded RNA (dsRNA).

What causes genes to turn on or off?

Gene regulation can occur at any point during gene expression, but most commonly occurs at the level of transcription (when the information in a gene’s DNA is transferred to mRNA). Signals from the environment or from other cells activate proteins called transcription factors.

Where is RNA located?

There are two types of nucleic acids which are polymers found in all living cells. Deoxyribonucleic Acid (DNA) is found mainly in the nucleus of the cell, while Ribonucleic Acid (RNA) is found mainly in the cytoplasm of the cell although it is usually synthesized in the nucleus.

Why is Mirna important?

MicroRNAs (miRNAs) are a class of small, endogenous RNAs of 21–25 nucleotides (nts) in length. They play an important regulatory role in animals and plants by targeting specific mRNAs for degradation or translation repression.

What is RNA silencing process?

RNA silencing or RNA interference refers to a family of gene silencing effects by which gene expression is negatively regulated by non-coding RNAs such as microRNAs. … RNA silencing mechanisms are highly conserved in most eukaryotes.