PMID- 22850217
OWN - NLM
STAT- MEDLINE
DCOM- 20130321
LR  - 20120917
IS  - 1095-6840 (Electronic)
IS  - 0016-6480 (Linking)
VI  - 179
IP  - 1
DP  - 2012 Oct 1
TI  - The RNA-binding protein xCIRP2 is involved in apoptotic tail regression during 
      metamorphosis in Xenopus laevis tadpoles.
PG  - 14-21
LID - S0016-6480(12)00292-4 [pii]
LID - 10.1016/j.ygcen.2012.07.017 [doi]
AB  - Frog metamorphosis induced by thyroid hormone (TH) involves not only cell 
      proliferation and differentiation in reconstituted organs such as limbs, but also 
      apoptotic cell death in degenerated organs such as tails. However, the molecular 
      mechanisms directing the TH-dependent cell fate determination remain unclear. We 
      have previously identified from newts an RNA-binding protein (nRBP) acting as the 
      regulator governing survival and death in germ cells during spermatogenesis. To 
      investigate the molecular events leading the tail resorption during 
      metamorphosis, we analyzed the expression, the functional role in apoptosis, and 
      the regulation of xCIRP2, a frog homolog of nRBP, in tails of Xenopus laevis 
      tadpoles. At the prometamorphic stage, xCIRP2 protein is expressed in fibroblast, 
      epidermal, nerve, and muscular cells and localized in their cytoplasm. When 
      spontaneous metamorphosis progressed, the level of xCIRP2 mRNA remained unchanged 
      but the amount of the protein decreased. In organ cultures of tails at the 
      prometamorphic stage, xCIRP2 protein decreased before their lengths shortened 
      during TH-dependent metamorphosis. The inhibition of calpain or proteasome 
      attenuated the TH-induced decrease of xCIRP2 protein in tails, impairing their 
      regression. These results suggest that xCIRP2 protein is downregulated through 
      calpain- and proteasome-mediated proteolysis in response to TH at the onset of 
      metamorphosis, inducing apoptosis in tails and thereby degenerating them.
CI  - Copyright (c) 2012 Elsevier Inc. All rights reserved.
FAU - Eto, Ko
AU  - Eto K
AD  - Department of Biological Sciences, Graduate School of Science and Technology, 
      Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan. 
      etoko@gpo.kumamoto-u.ac.jp
FAU - Iwama, Tomoyuki
AU  - Iwama T
FAU - Tajima, Tatsuya
AU  - Tajima T
FAU - Abe, Shin-ichi
AU  - Abe S
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20120728
PL  - United States
TA  - Gen Comp Endocrinol
JT  - General and comparative endocrinology
JID - 0370735
RN  - 0 (CIRP2 protein, Xenopus)
RN  - 0 (RNA-Binding Proteins)
RN  - 0 (Thyroid Hormones)
RN  - 0 (Xenopus Proteins)
SB  - IM
MH  - Animals
MH  - Apoptosis/*physiology
MH  - Cell Differentiation
MH  - Female
MH  - Gene Expression Regulation, Developmental
MH  - Larva/cytology/genetics/growth & development/metabolism
MH  - Metamorphosis, Biological/genetics/*physiology
MH  - RNA-Binding Proteins/*physiology
MH  - Tail/*cytology/metabolism
MH  - Thyroid Hormones/physiology
MH  - Xenopus Proteins/*physiology
MH  - Xenopus laevis/genetics/growth & development/metabolism
EDAT- 2012/08/02 06:00
MHDA- 2013/03/22 06:00
CRDT- 2012/08/02 06:00
PHST- 2012/01/24 00:00 [received]
PHST- 2012/07/10 00:00 [revised]
PHST- 2012/07/13 00:00 [accepted]
PHST- 2012/08/02 06:00 [entrez]
PHST- 2012/08/02 06:00 [pubmed]
PHST- 2013/03/22 06:00 [medline]
AID - S0016-6480(12)00292-4 [pii]
AID - 10.1016/j.ygcen.2012.07.017 [doi]
PST - ppublish
SO  - Gen Comp Endocrinol. 2012 Oct 1;179(1):14-21. doi: 10.1016/j.ygcen.2012.07.017. 
      Epub 2012 Jul 28.