The fully linked HTML version of this article has now been published.
JCS ePress
online publication date 4 Dec 2002
doi: 10.1242/jcs.00243
Research Article
Functional interaction of megalin with the megalin-binding protein (MegBP), a novel tetratrico peptide repeat-containing adaptor molecule
Helle Heibroch Petersen,
Jan Hilpert,
Daniel Militz,
Valerie Zandler,
Christian Jacobsen,
Anton J.M. Roebroek,
and
Thomas E. Willnow*
* Author for correspondence (e-mail: willnow{at}mdc-berlin.de)
Megalin is a member of the LDL receptor gene family that plays an important role in forebrain development and in cellular vitamin D metabolism through endocytic uptake of vitamin D metabolites. Similar to other receptors in this gene family, megalin is believed to functionally interact with intracellular proteins through adaptors that bind to the receptor tail and regulate its endocytic and signal transducing activities. Using yeast two-hybrid screens, we identified a novel scaffold protein with tetratrico peptide repeats, the megalin-binding protein (MegBP) that associates with the receptor. The binding site of MegBP was mapped to an N-terminal region on the receptor tail harboring a proline-rich peptide element. MegBP binding did not block the endocytic activity of the receptor; however, overexpression resulted in cellular lethality. In further screens, we identified proteins that bound to MegBP and thus might be recruited to the megalin tail. MegBP-interacting partners included several transcriptional regulators such as the SKI-interacting protein (SKIP), a co-activator of the vitamin D receptor. These finding suggest a model whereby megalin directly participates in transcriptional regulation through controlled sequestration or release of transcription factors via MegBP.
This article has been cited by other articles:

|
 |

|
 |
 
U. Anzenberger, N. Bit-Avragim, S. Rohr, F. Rudolph, B. Dehmel, T. E. Willnow, and S. Abdelilah-Seyfried
Elucidation of megalin/LRP2-dependent endocytic transport processes in the larval zebrafish pronephros
J. Cell Sci.,
May 15, 2006;
119(10):
2127 - 2137.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. S. Dusso, A. J. Brown, and E. Slatopolsky
Vitamin D
Am J Physiol Renal Physiol,
July 1, 2005;
289(1):
F8 - F28.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Marschang, J. Brich, E. J. Weeber, J. D. Sweatt, J. M. Shelton, J. A. Richardson, R. E. Hammer, and J. Herz
Normal Development and Fertility of Knockout Mice Lacking the Tumor Suppressor Gene LRP1b Suggest Functional Compensation by LRP1
Mol. Cell. Biol.,
May 1, 2004;
24(9):
3782 - 3793.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Nagai, T. Meerloo, T. Takeda, and M. G. Farquhar
The Adaptor Protein ARH Escorts Megalin to and through Endosomes
Mol. Biol. Cell,
December 1, 2003;
14(12):
4984 - 4996.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. May, H. H. Bock, and J. Herz
Integration of Endocytosis and Signal Transduction by Lipoprotein Receptors
Sci. Signal.,
April 1, 2003;
2003(176):
pe12 - pe12.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. A. McCarthy and W. S. Argraves
Megalin and the neurodevelopmental biology of sonic hedgehog and retinol
J. Cell Sci.,
March 15, 2003;
116(6):
955 - 960.
[Abstract]
[Full Text]
[PDF]
|
 |
|
© The Company of Biologists Ltd 2002