Typical Plane Gene -

A typical plant gene has the following regions beginning with the 5'-end:
(i)promoter (for transcription initiation),
(ii) enhancer/silencer (concerned with regulation),
(iii) transcriptional start or cap site,
(iv) an untranslated region or leader sequence,
(v) initiation codon,
(vi) exons,
(vii) introns,
(viii) the stop codon(s),
(ix) a second untranslated region and, finally,
(x) a poly(A) tail, which is typically G/AATAA(A)n.

The end of gene coding sequence is specified by the chain termination codon TAG (in mRNA, UAG) or one of the other two nonsense codons (TAA and-TGA). TAG is followed by a stretch of nontranslated region and at the end is present the polyadenylation site, which denotes the end of transcription.

Many proteins either move across membranes or become inserted into them. Genes encoding such proteins have at their 5'-ends' (immediately after the initiation codon ATG) a coding sequence, which encodes a signal peptide. The signal peptides are cleaved, after the protein has been translocated to the desired location, to generate the mature functional proteins.