Gene silencing and sex determination by programmed DNA elimination in parasitic nematodes.
Maintenance of genome integrity is essential. However, programmed DNA elimination removes specific DNA sequences from the genome during development. DNA elimination occurs in unicellular ciliates and diverse metazoa ranging from nematodes to vertebrates. Two distinct groups of nematodes use DNA elimination to silence germline-expressed genes in the soma (ascarids) or for sex determination (Strongyloides spp.). Data suggest that DNA elimination likely evolved independently in these nematodes. Recent studies indicate that differential CENP-A deposition within chromosomes defines which sequences are retained and lost during Ascaris DNA elimination. Additional studies are needed to determine the distribution, functions, and mechanisms of DNA elimination in nematodes.
Department Evolutionary Biology, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany.
Adrian
A
Streit
Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, United States.
Jianbin
J
Wang
Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, United States.
Yuanyuan
Y
Kang
Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, United States. Electronic address: richard.davis@ucdenver.edu.
Richard E
RE
Davis
D000818:Animals; D001200:Ascaris / Q000235:genetics* / Q000502:physiology; D001483:Base Sequence / Q000235:genetics*; D000076247:Centromere Protein A / Q000378:metabolism; D016054:DNA, Protozoan / Q000235:genetics; D005260:Female; D020868:Gene Silencing / Q000502:physiology*; D008297:Male; D017384:Sequence Deletion / Q000235:genetics*; D019849:Sex Determination Processes / Q000235:genetics*; D013321:Strongyloides / Q000235:genetics* / Q000502:physiology
D000076247:Centromere Protein A; D016054:DNA, Protozoan