Expression of class II molecules by B cells is down-regulated by IFN- .

TLS Online TPP Program

#Id: 3594

#Unit 3. Fundamental Processes

In 1961 Marshall Nirenberg and Heinrich Matthaei reported the first breakthrough in reading nucleotide codon in amino acid frame.

TLS Online TPP Program

#Id: 3596

#Unit 3. Fundamental Processes

Nirenberg and Matthaei therefore concluded that the triplet codon UUU encodes phenylalanine, poly(C) proline (polyproline), polyadenylate, poly(A), encodes polylysine.

TLS Online TPP Program

#Id: 3597

#Unit 3. Fundamental Processes

“Dictionary” of amino acid code words in mRNAs.

TLS Online TPP Program

#Id: 3599

#Unit 3. Fundamental Processes

The third base of each codon plays a lesser role in specifying an amino acid than the first two.

TLS Online TPP Program

#Id: 3600

#Unit 3. Fundamental Processes

All the amino acids except methionine and tryptophan have more than one codon.

TLS Online TPP Program

#Id: 3601

#Unit 3. Fundamental Processes

In most cases, codons that specify the same amino acid differ only at the third base.