Question

In 1964, Nirenberg and Leder used the triplet binding assay to determine specific codon assignments. A complex of which of the following components was trapped in the nitrocellulose filter?

A) charged tRNA, RNA triplet, and ribosome
B) ribosomes and DNA
C) sense and antisense strands of DNA
D) uncharged tRNAs and ribosomes
E) free tRNAs

Answer 1

In 1964, Nirenberg and Leder used the triplet binding assay to determine that a compound of charged A) tRNA, RNA triplet, and ribosome could be trapped in a nitrocellulose filter, thus proving codon assignments within the genetic code.

Step-by-step explanation:

In 1964, Nirenberg and Leder's experiment using the triplet binding assay was pivotal in deciphering the genetic code. They found that the formation of a complex, which includes charged transfer RNA (tRNA), an RNA triplet, and a ribosome, could be trapped by a nitrocellulose filter. This finding confirmed that triplets of RNA would bind to ribosomes, which in turn would bind to corresponding aminoacyl-tRNAs.

The resulting three-part complex comprising the ribosome, RNA triplet, and charged tRNA remained on the filter, allowing them to then identify which amino acid corresponded to which triplet code.

The success of Nirenberg and Leder's triplet binding assay subsequently enabled a more profound understanding of the genetic code and the synthesis of proteins. Their methodology also leveraged the understanding that ribosomes would not pass through the filter but aminoacyl-tRNAs would, evidence that pointed to the specificity of the tRNA-ribosome complex in recognizing the correct codons during protein synthesis.