Translation in plant cells is the process by which proteins are made from messenger RNA (mRNA). It occurs in the cytoplasm and sometimes inside chloroplasts and mitochondria, which have their own ribosomes. Here’s how it happens, step by step:
- Initiation
- The mRNA, which carries the genetic code from the nucleus, binds to a ribosome (a complex made of rRNA and proteins).
- A specific transfer RNA (tRNA) molecule carrying the amino acid methionine recognizes the start codon (AUG) on the mRNA.
- The small and large ribosomal subunits join together to form a complete ribosome ready for protein synthesis.
- Elongation
- The ribosome reads the mRNA codons (three-base sequences).
- Each codon is matched by a complementary anticodon on a tRNA carrying the correct amino acid.
- The ribosome links amino acids together with peptide bonds, forming a growing polypeptide chain.
- After the amino acid is added, the ribosome moves to the next codon.
- Termination
- When the ribosome reaches a stop codon (UAA, UAG, or UGA), no tRNA matches it.
- Instead, a release factor binds to the ribosome, causing the completed protein to be released.
- The ribosome then separates from the mRNA.
- Post-translation
- The new protein may fold into its functional shape with the help of chaperone proteins.
- It may also undergo modifications (like adding sugars or phosphate groups) before being transported to where it’s needed — such as the cell membrane, chloroplasts, or vacuoles.
In summary, translation in plants works just like in other eukaryotes — converting genetic information from mRNA into functional proteins, which perform vital roles in growth, metabolism, and development.