TY  - JOUR
N1  - Copyright of this article belongs to The American Society for Microbiology.
ID  - open1997
UR  - http://dx.doi.org/10.1091/mbc.E16-07-0485
IS  - 8
A1  - Upadhyay, Udita
A1  - Srivastava, Suchita
A1  - Khatri, Indu
A1  - Nanda, Jagpreet Singh
A1  - Subramanian, Srikrishna
A1  - Arora, Amit
A1  - Singh, Jagmohan
Y1  - 2017///
N2  - Inactivation of retrotransposons is accompanied by the emergence of centromere-binding protein-B (CENPB) in Schizosaccharomyces, as well as in metazoans. The RNA interference (RNAi)-induced transcriptional silencing (RITS) complex, comprising chromodomain protein-1 (Chp1), Tas3 (protein with unknown function), and Argonaute (Ago1), plays an important role in RNAi-mediated heterochromatinization. We find that whereas the Ago1 subunit of the RITS complex is highly conserved, Tas3 is lost and Chp1 is truncated in Schizosaccharomyces cryophilus and Schizosaccharomyces octosporus We show that truncated Chp1 loses the property of heterochromatin localization and silencing when transformed in Schizosaccharomyces pombe Furthermore, multiple copies of CENPB, related to Tc1/mariner and Tc5 transposons, occur in all Schizosaccharomyces species, as well as in humans, but with loss of transposase function (except Schizosaccharomyces japonicus). We propose that acquisition of Tc1/mariner and Tc5 elements by horizontal transfer in S. pombe (and humans) is accompanied by alteration of their function from a transposase/endonuclease to a heterochromatin protein, designed to suppress transposon expression and recombination. The resulting redundancy of RITS may have eased the selection pressure, resulting in progressive loss or truncation of tas3 and chp1 genes in S. octosporus and S. cryophilus and triggered similar evolutionary dynamics in the metazoan orthologues.
PB  - The American Society for Microbiology
JF  - Molecular Biology of the Cell
VL  - 28
SN  - 1059-1524
TI  - Ablation of RNA interference and retrotransposons accompany acquisition and evolution of transposases to heterochromatin protein CENPB
SP  - 1132
EP  - 1146
ER  -