True about genetic code
UGA is a stop codon, but in special circumstance, it stands for seleno-cysteine the codon AUG both codes for methionine and serves as an initiation site: the first AUG in a mRNA&;s coding region is where translation into protein begins.Ref: DM Vasudevan, 7th edition, page no: 599
AUA codes for methionine in mitochondria
UGA codes for selenocysteine
AUG codes for initiator codon in mammalian cell
AGA & AGG act as chain terminator in mammalian
Metabolism of nucleic acids