RNA STRUCTURE AND FUNCTION

PRACHEE RAJPUTM.Sc 1st Sem

Department Of Zoology And Applied AquacultureBrakatullah University Bhopal

synopsis

IntroductionCentral Dogma Protein SynthesisTypes Of RNAFunction Of RNAConclusion

CENTRAL DOGMA

PROTEIN SYNTHESIS

Transcription Translation

Types of rna

In all prokaryotic and eukaryotic organisms, three main classes of RNA molecules exist :

Messenger RNA (m RNA)Transfer RNA (tRNA)Ribosomal RNA (r RNA)

MESSENGER rna (M-RNA)

Comprises only 5% of the RNA in the cellMost heterogeneous in size and base sequenceAll members of the class function as

Messengers carrying the information in a gene to the protein synthesizing machinery.

Transfer rna (t-rna)

Transfer RNA are the smallest of three major species of RNA molecules.They have 74-94 nucleotide residues.They are synthesized by the nuclear processing of a precursor molecule.They transfer the amino acids from cytoplasm to the protein synthesizing machinery, hence called, soluble RNA or S RNA.

Ribosomal rna(r-rna)

All of the ribosomal RNA molecules except the 55 r RNA are processed from a single 455 precursor RNA molecule in the nucleus.

FUNCTION OF RNA

m RNA carries a copy of the instruction from the DNA in the nucleus to the ribosome r RNA is a major component op ribosome-the site of protein synthesis t-RNA carries the amino acids which are added to the polypeptide chain (protein) being synthesized.

conclusion

RNA exists in several different single stranded structure most of which are directly involved in protein synthesis or its regulation.