0845 numbers, for example, are free to call for up to an hour, during the inclusive minutes of your call package if you're a BT customer. Yet call an 0844 number and you'll be charged up to 5.1p/minute, plus a connection fee of up to 15p.
The resulting mRNA is a single-stranded copy of the gene, which next must be translated into a protein molecule. During translation, which is the second major step in gene expression, the mRNA is read according to the genetic code, which relates the DNA sequence to the amino acid sequence in proteins (Figure 2).
The vector itself is generally a DNA sequence that consists of an insert (transgene) and a larger sequence that serves as the backbone of the vector. The purpose of a vector which transfers genetic information to another cell is typically to isolate, multiply, or express the insert in the target cell.