PMID- 12416728
OWN - NLM
STAT- MEDLINE
DCOM- 20030430
LR  - 20131121
IS  - 0171-9335 (Print)
IS  - 0171-9335 (Linking)
VI  - 81
IP  - 9
DP  - 2002 Sep
TI  - External GTP binding and induction of cell division in starved Tetrahymena 
      thermophila.
PG  - 517-24
AB  - The extracellular nucleotide, guanosine 5'-triphosphate (GTP) is known to be a 
      chemorepellent for ciliated protozoa such as Paramecium and Tetrahymena. Here, we 
      studied the surface localization of GTP binding sites and also its effects on the 
      cell division of Tetrahymena thermophila. When a ribose-modified and fluorescent 
      analog of GTP, 2'-(or -3')-O-trinitrophenyl (TNP)-GTP was added to the cells 
      starved in non-nutrient buffer, a remarkable fluorescence was observed at the 
      compound cilia of the oral area, while it was weak at other cilia and the somatic 
      membrane. Following transfer of the cells to the starvation medium, the intensity 
      of TNP-GTP fluorescence at the oral area gradually increased and was saturated at 
      3-4 hours. Addition of GTP to the starved cell induced not only an avoiding 
      reaction in swimming, but also induced a synchronous cell division that occurred 
      2 hours later. An attempt to search for other stimuli, which induced cell 
      division, revealed that mechanical stimulation by a short period of 
      centrifugation was almost as effective as the addition of GTP. The supernatant 
      after centrifugation had the ability to induce cell division, and such activity 
      was abolished after the supernatant was treated with the phosphatase, apyrase, 
      suggesting the release of GTP by the mechanical stimulation. These results 
      indicate that the released GTP binds mainly to the oral area and this then 
      induces the cell division of starved T. thermophila.
FAU - Iwamoto, Masaaki
AU  - Iwamoto M
AD  - Division of Biophysical Engineering, Graduate School of Engineering Science, 
      Osaka University, Toyonaka, Japan.
FAU - Nakaoka, Yasuo
AU  - Nakaoka Y
LA  - eng
PT  - Journal Article
PL  - Germany
TA  - Eur J Cell Biol
JT  - European journal of cell biology
JID - 7906240
RN  - 86-01-1 (Guanosine Triphosphate)
RN  - 97122-52-6 (2',3'-O-(2,4,6-trinitrocyclohexadienylidene)guanosine 
      5'-triphosphate)
RN  - SY7Q814VUP (Calcium)
SB  - IM
MH  - Animals
MH  - Calcium/metabolism
MH  - Cell Division/*physiology
MH  - Fluorescence
MH  - Guanosine Triphosphate/*analogs & derivatives/*metabolism
MH  - Signal Transduction/physiology
MH  - Tetrahymena thermophila/*metabolism
EDAT- 2002/11/06 04:00
MHDA- 2003/05/06 05:00
CRDT- 2002/11/06 04:00
PHST- 2002/11/06 04:00 [pubmed]
PHST- 2003/05/06 05:00 [medline]
PHST- 2002/11/06 04:00 [entrez]
AID - S0171-9335(04)70253-8 [pii]
AID - 10.1078/0171-9335-00267 [doi]
PST - ppublish
SO  - Eur J Cell Biol. 2002 Sep;81(9):517-24. doi: 10.1078/0171-9335-00267.