Several small proteins called single strand binding proteins (SSB) temporarily bind to each facet and keep them separated. An enzyme referred to as DNA ligase seals up the fragments into one lengthy continuous strand. In the cells of those organisms, the DNA is twisted around bead-like proteins referred to as histones. Other cells go through several rounds of cell division and cease (including specialized cells, like these in your brain, muscles and heart). All mRNA molecules begin with the beginning codon AUG. UGA, UAA and UAG are stop codons; cease codons haven't any corresponding tRNA molecules. The genetic code desk above is for mRNA and specifies the bases in the primary, second and third positions of the codon with their corresponding amino acids. We know this sequence of amino acids by using a desk of the genetic code. Let's read the amino acid specified by the mRNA codon, AUG, using the table at the top of the web page. First, place your left finger on the first place codon (A), in the primary column of the desk.