Operons in C. elegans: polycistronic mRNA precursors are processed by trans-splicing of SL2 to downstream coding regions

Cell. 1993 May 7;73(3):521-32. doi: 10.1016/0092-8674(93)90139-h.


The mRNAs of six C. elegans genes are known to be trans-spliced to SL2. We report here that a similarly oriented gene is located 100-300 bp upstream of each. We present evidence that the genes in these clusters are cotranscribed and downstream mRNAs are formed by cleavage at the polyadenylation site and trans-splicing. From one three-gene cluster we isolated cDNA clones representing both polycistronic RNAs and mRNAs polyadenylated at the free 3' end created by trans-splicing, suggesting that polycistronic RNAs can be processed by trans-splicing. Several experiments indicate that SL2 trans-splicing is a consequence of a gene's downstream location in an operon. In particular, when an SL1-accepting gene was moved to a downstream location, its mRNA was trans-spliced largely to SL2. The possible regulatory significance of cotranscription of C. elegans genes is discussed.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Caenorhabditis elegans / genetics*
  • Cloning, Molecular
  • Genes*
  • Heat-Shock Proteins / genetics
  • Molecular Sequence Data
  • Multigene Family
  • Oligodeoxyribonucleotides
  • Operon*
  • Plasmids
  • Poly A / genetics*
  • Polymerase Chain Reaction / methods
  • RNA Precursors / genetics*
  • RNA Splicing*
  • RNA, Messenger / genetics*
  • Restriction Mapping
  • Transcription, Genetic


  • Heat-Shock Proteins
  • Oligodeoxyribonucleotides
  • RNA Precursors
  • RNA, Messenger
  • Poly A

Associated data

  • GENBANK/L12247
  • GENBANK/L12348
  • GENBANK/L33709
  • GENBANK/S60899
  • GENBANK/S60900
  • GENBANK/S60901
  • GENBANK/S60902
  • GENBANK/S60903
  • GENBANK/S60904
  • GENBANK/S60905
  • GENBANK/S60924