PMID- 11907038
OWN - NLM
STAT- MEDLINE
DCOM- 20020702
LR  - 20210209
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 277
IP  - 22
DP  - 2002 May 31
TI  - Telomeric localization of the vertebrate-type hexamer repeat, (TTAGGG)n, in the 
      wedgeshell clam Donax trunculus and other marine invertebrate genomes.
PG  - 19839-46
AB  - The hexamer repeat sequence (TTAGGG)(n), found at the ends of all vertebrate 
      chromosomes, was previously identified as the main building element of one member 
      of a HindIII satellite DNA family characterized in the genome of the bivalve 
      mollusc Donax trunculus. It was also found in 22 perfect tandem repeats in a 
      cloned junction region juxtaposed to the proper satellite sequence, from which 
      the DNA tract encompassing the clustered tandem copies was excised and subcloned. 
      Here, the chromosomal distribution of (TTAGGG)(n) sequences in the Donax was 
      studied by the sensitivity to Bal31 exonuclease digestion, fluorescence in situ 
      hybridization (FISH) on metaphase chromosomes and rotating-field gel 
      electrophoresis. To verify the occurrence of the hexamer repeat in the genomes of 
      taxonomically related molluscs and other marine invertebrates, genomic DNA from 
      the mussel Mytilus galloprovincialis and the echinoderm Holothuria tubulosa was 
      also analyzed. The kinetics of Bal31 hydrolysis of high molecular mass DNA from 
      the three marine invertebrates revealed a marked decrease over time of the 
      hybridization with the cloned (TTAGGG)(22) sequence, concomitantly with a 
      progressive shortening of the positively reacting DNA fragments. This revealed a 
      marked susceptibility to exonuclease consistent with terminal positioning on the 
      respective chromosomal DNAs. In full agreement, FISH results with the 
      (TTAGGG)(22) probe showed that the repeat appears located in telomeric regions in 
      all chromosomes of both bivalve molluscs. The presence of (TTAGGG)(n) repeat 
      tracts in marine invertebrate telomeres points to its wider distribution among 
      eukaryotic organisms and suggests an ancestry older than originally presumed from 
      its vertebrate distinctiveness.
FAU - Plohl, Miroslav
AU  - Plohl M
AD  - Department of Molecular and Cell Biology, Institut de Biologia Molecular de 
      Barcelona, CSIC, E-08034 Barcelona, Spain.
FAU - Prats, Eva
AU  - Prats E
FAU - Martinez-Lage, Andres
AU  - Martinez-Lage A
FAU - Gonzalez-Tizon, Ana
AU  - Gonzalez-Tizon A
FAU - Mendez, Josefina
AU  - Mendez J
FAU - Cornudella, Luis
AU  - Cornudella L
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20020320
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 9007-49-2 (DNA)
RN  - EC 3.1.- (Endodeoxyribonucleases)
RN  - EC 3.1.11.- (exonuclease Bal 31)
SB  - IM
MH  - Animals
MH  - Base Sequence
MH  - Blotting, Southern
MH  - Chromosomes/ultrastructure
MH  - Cloning, Molecular
MH  - DNA/metabolism
MH  - Dose-Response Relationship, Drug
MH  - Endodeoxyribonucleases/metabolism
MH  - *Genome
MH  - In Situ Hybridization, Fluorescence
MH  - Kinetics
MH  - Microscopy, Fluorescence
MH  - Models, Genetic
MH  - Molecular Sequence Data
MH  - Mollusca
MH  - Sea Cucumbers
MH  - Telomere/*metabolism/*ultrastructure
MH  - Time Factors
EDAT- 2002/03/22 10:00
MHDA- 2002/07/03 10:01
CRDT- 2002/03/22 10:00
PHST- 2002/03/22 10:00 [pubmed]
PHST- 2002/07/03 10:01 [medline]
PHST- 2002/03/22 10:00 [entrez]
AID - S0021-9258(20)85052-2 [pii]
AID - 10.1074/jbc.M201032200 [doi]
PST - ppublish
SO  - J Biol Chem. 2002 May 31;277(22):19839-46. doi: 10.1074/jbc.M201032200. Epub 2002 
      Mar 20.