Messenger RNA (mRNA) is synthesized from a gene segment of DNA which ultimately contains the information on the primary sequence of amino acids in a protein to be synthesized. The genetic code as translated is for m-RNA not DNA. The messenger RNA carries the code into the cytoplasm where protein synthesis occurs.
Genetic Code:
Each gene (or distinct segment) on DNA contains instructions for making one specific protein with order of amino acids coded by the precise sequence of heterocyclic amines on the nucleotides. Since proteins have a variety of functions including those of enzymes mistakes in the primary sequence of amino acids in proteins may have lethal effects.
How can a polymeric nucleotide with only four different heterocyclic amines specify the sequence of 20 or more different amino acids? If each nucleotide coded for a single amino acid, then obviously only 4 of the 20 amino acids could be accommodated. If the nucleotides were used in groups of two, there are 16 different combinations possible which is still inadequate.
It has been determined that the genetic code is actually based upon triplets of nucleotides which provide 64 different codes using the 4 nucleotides. During the 1960's, a tremendous effort was devoted to proving that the code was read as triplets, and also to solving the genetic code. The genetic code was originally translated for the bacteria E. Coli, but its universality has since been established. The genetic code is "read" from a type of RNA called messenger RNA (mRNA). Each nucleotide triplet, called a codon, can be "read" and translated into an amino acid to be incorporated into a protein being synthesized. The genetic code is shown in Figure 7.
Several distinctive features of the genetic code are clearly evident. First, all of the 64 codons or triplets have a known function, with 61 coding for amino acids and the other 3 serving as a stop or termination signal for protein synthesis. Secondly, the code is degenerate, meaning that there are usually several codons for each amino acid. Only methionine and tryptophan have a single codon. More specifics on the importance of the degeneracy of the genetic code will be discussed in a later section.
The basic unit of messenger RNA (mRNA) is a nucleotide, which consists of a phosphate group, a ribose sugar, and one of four nitrogenous bases (adenine, cytosine, guanine, or uracil). mRNA is transcribed from DNA and carries the genetic information from the nucleus to the ribosome, where it is translated into a protein.
mRNA (messenger RNA) is the form of RNA that carries the genetic code from DNA in the cell nucleus to the ribosomes in the cytoplasm, where proteins are synthesized. This process is known as transcription.
Messenger RNA (mRNA) is the type of RNA that carries the genetic information from the DNA in the nucleus to the ribosomes in the cytoplasm, where proteins are synthesized.
Messenger RNA is synthesized in the nucleus of a cell during a process called transcription. It is created from a DNA template by an enzyme called RNA polymerase. Once it is produced, the messenger RNA can then move out of the nucleus and into the cytoplasm to direct the synthesis of proteins.
Messenger RNA (mRNA) carries the instructions from the DNA in the nucleus to the ribosomes in the cytoplasm, where protein synthesis takes place.
Two types of RNA are messenger RNA (mRNA), which carries genetic information from the DNA to the ribosome for protein synthesis, and transfer RNA (tRNA), which brings amino acids to the ribosome during protein synthesis.
Amino acids are the basic units of messenger RNA. mRNA is synthesized from DNA and is a single stranded molecule.
DNA and RNA
Messenger RNA (mRNA) is a copy of the DNA message that is transcribed in the nucleus and can be translated into proteins in the cytoplasm. It carries the genetic information from the DNA to the ribosomes where protein synthesis occurs.
DNA and RNA
transfer RNA messenger RNA Ribosomal RNA
mRNA (messenger RNA) is the form of RNA that carries the genetic code from DNA in the cell nucleus to the ribosomes in the cytoplasm, where proteins are synthesized. This process is known as transcription.
The type of RNA that brings instructions from DNA in the nucleus to the cytoplasm is messenger RNA or mRNA.
mRNA - messenger RNA tRNA - transfer RNA rRNA - ribosomal RNA
Messenger RNA Transcription RNA Ribosomal RNA
Messenger RNA (mRNA) is the type of RNA that carries the genetic information from the DNA in the nucleus to the ribosomes in the cytoplasm, where proteins are synthesized.
messenger RNA (mRNA)
messenger rna