spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online 28 September 2005
doi: 10.1242/dev.02050

Development 132, 4675-4685 (2005)
Published by The Company of Biologists 2005
This Article
Right arrow Summary Freely available
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Material
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Thangaraju, M.
Right arrow Articles by Sterneck, E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Thangaraju, M.
Right arrow Articles by Sterneck, E.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

C/EBP{delta} is a crucial regulator of pro-apoptotic gene expression during mammary gland involution

Muthusamy Thangaraju1,*, Martina Rudelius2, Brian Bierie3,{dagger}, Mark Raffeld2, Shikha Sharan1, Lothar Hennighausen3, A-Mei Huang1,{ddagger} and Esta Sterneck1,§

1 Laboratory of Protein Dynamics and Signaling, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
2 Laboratory of Pathology, National Cancer Institute, National Institute of Health, Bethesda MD 20892, USA
3 Laboratory of Genetics and Physiology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Health, Bethesda, MD 20892, USA



View larger version (133K):

[in a new window]
  		Fig. 1. C/EBP{delta} is expressed in luminal epithelial cells. Immunohistochemistry of C/EBP{delta} in wild-type and C/EBP{delta} null mammary glands at the indicated time points of involution after 7 days of lactation. Representative sections at 400 x and 50 x original magnification are shown (insets). M, myoepithelial cells; solid arrows, positive stromal cells; open arrows, negative stromal cells.

 


View larger version (42K):

[in a new window]
  		Fig. 2. C/EBP{delta} and MMP3 expression in the mammary gland are dependent on STAT3. Northern analysis of the indicated genes in total RNA from mammary glands of mice with a floxed Stat3 allele and with or without the WAP-cre (WC) transgene during lactation (involution day 0) and 1-3 days after removal of the pups (two to four independent mice per group).

 


View larger version (129K):

[in a new window]
  		Fig. 3. Involution is delayed in C/EBP{delta} null mammary glands. Comparison of mammary gland histology during involution in wild-type (WT) and C/EBP{delta} null (KO) mice. (A) Representative photographs of sections from two mice per indicated time points (original magnification 50x). (B) Quantification of the areas occupied by adipocytes in mammary gland sections at days 1-4 of involution (three to four mice per time point). **P<0.01, ***P<0.01, *****P<0.00001, by two-way ANOVA with follow-up tests.

 


View larger version (105K):

[in a new window]
  		Fig. 4. Pro-apoptotic protein expression and activity are delayed in C/EBP{delta} null mammary glands. Western blot analysis of the indicated proteins in total protein extracts (50 µg each) from mammary glands of wild-type and C/EBP{delta} null mice on days 0-4 and 8 of involution.

 


View larger version (60K):

[in a new window]
  		Fig. 5. Involution-associated gene expression patterns are significantly altered in the absence of C/EBP{delta}. (A) Multiprobe ribonuclease protection assay of the indicated genes in total RNA from mammary glands of two mice per genotype and time point. Connecting lines were drawn as a visual aid. Shaded boxes indicate the time points of most significant differences between wild-type and C/EBP{delta} null glands. (B) Northern analysis of the indicated genes in total RNA from mammary glands during lactation (Inv d0) and 1-4 days after removal of the pups (two mice per group). (C) A selection of the data from panel B quantified by phosphoimaging and normalized to cyclophilin (CK18) or CK18 (IGFBP5, SGP2, p53) expression. (D) Northern analysis of the indicated genes in total RNA from mammary glands on days 0 and 1 of involution. Data shown are the phosphoimage quantifications of expression levels in four to five mice per data point normalized to cyclophilin expression. a.u., arbitrary units.

 


View larger version (23K):

[in a new window]
  		Fig. 6. C/EBP{delta} induces involution-related genes in HC11 cells and cooperates with p53 in inducing apoptosis. The non-transformed mouse mammary epithelial cell line HC11 was transiently transfected with constructs expressing the indicated proteins, and harvested after 2 days. (A) Northern analysis of the indicated genes in total RNA from representative samples are shown. (B) The flow cytometric quantification of arrested (G1 DNA content) and (C) apoptotic cells (sub-G1 DNA content) represents the means ± s.d. of six to eight samples from three to four independent experiments.

 


View larger version (13K):

[in a new window]
  		Fig. 7. Schematic representation of the gene expression events following C/EBP{delta} induction by the STAT3 pathway in involuting mouse mammary glands. Dashed lines indicate interactions that may be either direct or indirect. Solid lines indicate probable direct interactions.

 

Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?



© The Company of Biologists Ltd 2005