PMID- 10207110
OWN - NLM
STAT- MEDLINE
DCOM- 19990518
LR  - 20210526
IS  - 0270-7306 (Print)
IS  - 0270-7306 (Linking)
VI  - 19
IP  - 5
DP  - 1999 May
TI  - The human DNA ligase III gene encodes nuclear and mitochondrial proteins.
PG  - 3869-76
AB  - We provide evidence that the human DNA ligase III gene encodes a mitochondrial
      form of this enzyme. First, the DNA ligase III cDNA contains an in-frame ATG
      located upstream from the putative translation initiation start site. The DNA
      sequence between these two ATG sites encodes an amphipathic helix similar to
      previously identified mitochondrial targeting peptides. Second, recombinant green
      fluorescent protein harboring this sequence at its amino terminus was efficiently
      targeted to the mitochondria of Cos-1 monkey kidney cells. In contrast, native
      green fluorescent protein distributed to the cytosol. Third, a series of
      hemagglutinin-DNA ligase III minigene constructs were introduced into Cos-1
      cells, and immunocytochemistry was used to determine subcellular localization of 
      the epitope-tagged DNA ligase III protein. These experiments revealed that
      inactivation of the upstream ATG resulted in nuclear accumulation of the DNA
      ligase III protein, whereas inactivation of the downstream ATG abolished nuclear 
      localization and led to accumulation within the mitochondrial compartment.
      Fourth, mitochondrial protein extracts prepared from human cells overexpressing
      antisense DNA ligase III mRNA possessed substantially less DNA ligase activity
      than did mitochondrial extracts prepared from control cells. DNA end-joining
      activity was also substantially reduced in extracts prepared from antisense
      mRNA-expressing cells. From these results, we conclude that the human DNA ligase 
      III gene encodes both nuclear and mitochondrial enzymes. DNA ligase plays a
      central role in DNA replication, recombination, and DNA repair. Thus,
      identification of a mitochondrial form of this enzyme provides a tool with which 
      to dissect mammalian mitochondrial genome dynamics.
FAU - Lakshmipathy, U
AU  - Lakshmipathy U
AD  - Department of Pharmacology, University of Minnesota Medical School, Minneapolis, 
      Minnesota 55455, USA.
FAU - Campbell, C
AU  - Campbell C
LA  - eng
GR  - CA R29 CA61906/CA/NCI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Mol Cell Biol
JT  - Molecular and cellular biology
JID - 8109087
RN  - 0 (DNA, Mitochondrial)
RN  - 0 (Luminescent Proteins)
RN  - 0 (Nuclear Proteins)
RN  - 0 (Poly-ADP-Ribose Binding Proteins)
RN  - 0 (RNA, Antisense)
RN  - 0 (RNA, Messenger)
RN  - 0 (Recombinant Fusion Proteins)
RN  - 0 (Xenopus Proteins)
RN  - 147336-22-9 (Green Fluorescent Proteins)
RN  - EC 6.5.1.- (DNA Ligases)
RN  - EC 6.5.1.1 (DNA Ligase ATP)
RN  - EC 6.5.1.1 (DNA ligase III alpha protein, Xenopus)
RN  - EC 6.5.1.1 (LIG3 protein, human)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - COS Cells
MH  - Cloning, Molecular
MH  - DNA Ligase ATP
MH  - DNA Ligases/*genetics
MH  - DNA, Mitochondrial/genetics
MH  - Green Fluorescent Proteins
MH  - Humans
MH  - Immunohistochemistry
MH  - Luminescent Proteins/genetics
MH  - Mitochondria/*enzymology/genetics
MH  - Molecular Sequence Data
MH  - Nuclear Proteins/*genetics
MH  - Poly-ADP-Ribose Binding Proteins
MH  - RNA, Antisense/genetics
MH  - RNA, Messenger/genetics
MH  - Recombinant Fusion Proteins/genetics
MH  - Sequence Analysis, DNA
MH  - Transfection
MH  - Xenopus Proteins
PMC - PMC84244
EDAT- 1999/04/17 00:00
MHDA- 1999/04/17 00:01
CRDT- 1999/04/17 00:00
PHST- 1999/04/17 00:00 [pubmed]
PHST- 1999/04/17 00:01 [medline]
PHST- 1999/04/17 00:00 [entrez]
AID - 10.1128/MCB.19.5.3869 [doi]
PST - ppublish
SO  - Mol Cell Biol. 1999 May;19(5):3869-76. doi: 10.1128/MCB.19.5.3869.