The Pribnow box is an element in prokaryotic promoters that functions as a cis-acting element. Rho plays a role in terminating prokaryotic transcription. Sigma is the subunit of prokaryotic RNA polymerase responsible for recognizing and binding the prokaryotic promoter. U1 is a ribonucleoprotein involved in splicing eukaryotic premRNA.

The RNA product of the DNA template sequence GATCTAC, conventionally written, is 5′-GUAGAUC-3′. Nucleic acid sequences are conventionally written from 5′ to 3′. The template strand, 5′-GATCTAC-3′, is used as 3′CATCTAG-5′. The RNA product is complementary to the template strand (and identical to the coding strand), with U replacing T.

Genetic information is stored in chromosomes and transmitted to daughter cells through DNA replication. It is expressed through transcription to RNA and, in the case of mRNA, translated into proteins. The process of protein synthesis is known as translation, where the nucleotide sequence on mRNA is translated into an amino acid sequence. Alterations in the nucleotide sequence can result in incorrect amino acids being inserted into proteins, potentially causing disease or organism death. Immature proteins undergo folding and covalent modification to achieve their functional form. They are also targeted to their final intra- or extracellular destinations by signals present within the proteins themselves.

The genetic code serves as a dictionary that correlates a sequence of nucleotide bases with a sequence of amino acids. Each codon, which consists of three nucleotide bases, represents an individual "word" in the code. Codons are presented in the mRNA language of adenine (A), guanine (G), cytosine (C), and uracil (U), and their sequences are always written from the 5′-end to the 3′-end. The four nucleotide bases can combine in 64 different ways to form three-base codons. Some common amino acids are provided as examples in a table. The table can be used to translate any codon and determine the amino acids coded for by an mRNA sequence. The codon AUG serves as the initiation (start) codon for translation and codes for methionine. Three codons, UAA, UAG, and UGA, act as termination (stop or nonsense) codons, signaling the end of polypeptide synthesis when present in an mRNA sequence.

The genetic code is consistent across all living organisms, and any alteration in its meaning would likely result in lethal consequences.
Pribnow box is a cis-acting element in prokaryotic promoters. Rho is involved in the termination of prokaryotic transcription. Sigma is the subunit of prokaryotic RNA polymerase that recognizes and binds the prokaryotic promoter. U1 is a ribonucleoprotein involved in splicing of eukaryotic premRNA.
1.5. What is the sequence (conventionally written) of the RNA product of the DNA template sequence, GATCTAC, also conventionally written?
Correct answer = 5′-GUAGAUC-3′. Nucleic acid sequences are conventionally written 5′ to 3′. The template strand (5′-GATCTAC-3′) is used as 3′CATCTAG-5′. The RNA product is complementary to the template strand (and identical to the coding strand), with U replacing T.
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I. OVERVIEW
Genetic information, stored in the chromosomes and transmitted to daughter cells through DNA replication, is expressed through transcription to RNA and, in the case of messenger RNA (mRNA), subsequent translation into proteins (polypeptides) as shown in Figure 32.1. [Note: The proteome is the complete set of proteins expressed in a cell.] The process of protein synthesis is called translation because the “language” of the nucleotide sequence on the mRNA is translated into the language of an amino acid sequence. Translation requires a genetic code, through which the information contained in the nucleotide sequence is expressed to produce a specific amino acid sequence. Any alteration in the nucleotide sequence may result in an incorrect amino acid being inserted into the protein, potentially causing disease or even death of the organism. Newly made immature (nascent) proteins undergo a number of processes to achieve their functional form. They must fold properly, and misfolding can result in aggregation or degradation of the protein. Many proteins are covalently modified to alter their activities. Lastly, proteins are targeted to their final intra-or extracellular destinations by signals present in the proteins themselves.
II. THE GENETIC CODE
The genetic code is a “dictionary” that identifies the correspondence between a sequence of nucleotide bases and a sequence of amino acids. Each individual “word” in the code is composed of three nucleotide bases. These genetic words are called codons.
A. Codons
Codons are presented in the mRNA language of adenine (A), guanine (G), cytosine (C), and uracil (U). Their nucleotide sequences are always written from the 5′-end to the 3′-end. The four nucleotide bases are used to produce the three-base codons. Therefore, 64 different combinations of bases exist, taken three at a time (a triplet code), as shown in the table in Figure 32.2.
many common amino acids are shown as examples.
1.
How to translate a codon: This table can be used to translate any codon and, thus, to determine which amino acids are coded for by an mRNA sequence. For example, the codon AUG codes for methionine ([Met] see Fig. 32.2). [Note: AUG is the initiation (start) codon for translation.] Sixty-one of the 64 codons code for the 20 standard amino acids (see p. 1).
2.
Termination codons: Three of the codons, UAA, UAG, and UGA, do not code for amino acids but, rather, are termination (also called stop, or nonsense) codons. When one of these codons appears in an mRNA sequence, synthesis of the polypeptide coded for by that mRNA stops.
B. Characteristics
Usage of the genetic code is remarkably consistent throughout all living organisms. It is assumed that once the standard genetic code evolved in primitive organisms, any mutation (a permanent change in DNA sequence) that altered its meaning would have caused the alteration of most, if not all, protein sequences, resulting in lethality. Characteristics of the genetic code include the following.
1.