retrotransposon (class 1 transposon)

Introduction

• moves &/or multiplies in the genome by being transcribed to RNA, then back to DNA by reverse transcriptase
• evolution of autosomal retrogenes from X-linked progenitors compensates for X-chromosome silencing during male meiosis

3 main classes:

• viral:
  • encode reverse transcriptase
  • have long terminal repeats (LTRs)
  • similar to retroviruses
• LINEs:
  • encode reverse transcriptase
  • lack LTRs
  • transcribed by RNA polymerase 2
• nonviral superfamily:
  • do not code for reverse transcriptase
  • transcribed by RNA polymerase 3

More general terms

• transposon

Additional terms

• mammalian retrotransposon-derived protein
• retrotransposon gag domain-containing protein (RGAG)