TY - JOUR
T1 - Role of p38 in replication of Trypanosoma brucei kinetoplast DNA
AU - Liu, Beiyu
AU - Molina, Henrik
AU - Kalume, Dario
AU - Pandey, Akhilesh
AU - Griffith, Jack D.
AU - Englund, Paul T.
PY - 2006/7
Y1 - 2006/7
N2 - Trypanosomes have an unusual mitochondrial genome, called kinetoplast DNA, that is a giant network containing thousands of interlocked minicircles. During kinetoplast DNA synthesis, minicircles are released from the network for replication as θ-structures, and then the free minicircle progeny reattach to the network. We report that a mitochondrial protein, which we term p38, functions in kinetoplast DNA replication. RNA interference (RNAi) of p38 resulted in loss of kinetoplast DNA and accumulation of a novel free minicircle species named fraction S. Fraction S minicircles are so underwound that on isolation they become highly negatively supertwisted and develop a region of Z-DNA. p38 binds to minicircle sequences within the replication origin. We conclude that cells with RNAi-induced loss of p38 cannot initiate minicircle replication, although they can extensively unwind free minicircles.
AB - Trypanosomes have an unusual mitochondrial genome, called kinetoplast DNA, that is a giant network containing thousands of interlocked minicircles. During kinetoplast DNA synthesis, minicircles are released from the network for replication as θ-structures, and then the free minicircle progeny reattach to the network. We report that a mitochondrial protein, which we term p38, functions in kinetoplast DNA replication. RNA interference (RNAi) of p38 resulted in loss of kinetoplast DNA and accumulation of a novel free minicircle species named fraction S. Fraction S minicircles are so underwound that on isolation they become highly negatively supertwisted and develop a region of Z-DNA. p38 binds to minicircle sequences within the replication origin. We conclude that cells with RNAi-induced loss of p38 cannot initiate minicircle replication, although they can extensively unwind free minicircles.
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U2 - 10.1128/MCB.00369-06
DO - 10.1128/MCB.00369-06
M3 - Article
C2 - 16809774
AN - SCOPUS:33745844850
SN - 0270-7306
VL - 26
SP - 5382
EP - 5393
JO - Molecular and Cellular Biology
JF - Molecular and Cellular Biology
IS - 14
ER -