Telomerase is an enzyme that catalyzes the lengthening of telomeres. Transcription stops when the RNA polymerase reaches a stop codon. The aminoacyl-tRNA synthetases are responsible for forming the peptide bond between amino acids in a protein. Usually there are several ribosomes translating a single mRNA at the same time. Such a structure is called a polyribosome.
Ribosomes contain four different histone proteins.
Many transcription factors contain a DNA-binding domain.