Hgs (Hrs), a FYVE Domain Protein, Is Involved in Smad Signaling through Cooperation with SARA

ABSTRACT Smad proteins are effector molecules that transmit signals from the receptors for the transforming growth factor β (TGF-β) superfamily to the nucleus; of the Smad proteins, Smad2 and Smad4 are essential components for mouse early embryogenesis. We demonstrated that Hgs, a FYVE domain protein, binds to Smad2 in its C-terminal half and cooperates with another FYVE domain protein, the Smad anchor for receptor activation (SARA), to stimulate activin receptor-mediated signaling through efficient recruitment of Smad2 to the receptor. Furthermore, a LacZ knock-in allele of the C-terminal half-deletion mutant of mouse Hgs was created by gene targeting. The introduced mutation causes an embryonic lethality between embryonic days 8.5 and 10.5. Mutant cells showed significantly decreased responses to stimulation with activin and TGF-β. These findings suggest that the two FYVE domain proteins, Hgs and SARA, are prerequisites for receptor-mediated activation of Smad2.

[1]  F. Conlon,et al.  A primary requirement for nodal in the formation and maintenance of the primitive streak in the mouse. , 1994, Development.

[2]  J. Massagué.  TGF-beta signal transduction. , 1998, Annual review of biochemistry.

[3]  J. Massagué,et al.  Activation of signalling by the activin receptor complex , 1996, Molecular and cellular biology.

[4]  S. Willis,et al.  Formation and activation by phosphorylation of activin receptor complexes. , 1996, Molecular endocrinology.

[5]  A. Toker,et al.  Signalling through the lipid products of phosphoinositide-3-OH kinase , 1997, Nature.

[6]  P. Donahoe,et al.  The type I activin receptor ActRIB is required for egg cylinder organization and gastrulation in the mouse. , 1998, Genes & development.

[7]  J. Gerhart,et al.  Formation and function of Spemann's organizer. , 1997, Annual review of cell and developmental biology.

[8]  R. Scheller,et al.  Hrs-2 is an ATPase implicated in calcium-regulated secretion , 1997, Nature.

[9]  J. Wrana,et al.  Mads and Smads in TGFβ signalling , 1998 .

[10]  J. Wrana,et al.  The MAD-Related Protein Smad7 Associates with the TGFβ Receptor and Functions as an Antagonist of TGFβ Signaling , 1997, Cell.

[11]  Takeshi Imamura,et al.  Smad proteins exist as monomers in vivo and undergo homo‐ and hetero‐oligomerization upon activation by serine/threonine kinase receptors , 1998, The EMBO journal.

[12]  Liliana Attisano,et al.  SARA, a FYVE Domain Protein that Recruits Smad2 to the TGFβ Receptor , 1998, Cell.

[13]  A. Chawla,et al.  A functional PtdIns(3)P-binding motif , 1998, Nature.

[14]  C. Deng,et al.  The tumor suppressor SMAD4/DPC4 is essential for epiblast proliferation and mesoderm induction in mice. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[15]  C. Burd,et al.  Phosphatidylinositol(3)-phosphate signaling mediated by specific binding to RING FYVE domains. , 1998, Molecular cell.

[16]  P. Hoodless,et al.  MADR2 Is a Substrate of the TGFβ Receptor and Its Phosphorylation Is Required for Nuclear Accumulation and Signaling , 1996, Cell.

[17]  M. Komada,et al.  Growth factor-induced tyrosine phosphorylation of Hrs, a novel 115-kilodalton protein with a structurally conserved putative zinc finger domain , 1995, Molecular and cellular biology.

[18]  Kohei Miyazono,et al.  TGF-β signalling from cell membrane to nucleus through SMAD proteins , 1997, Nature.

[19]  N. Tanaka,et al.  STAM, signal transducing adaptor molecule, is associated with Janus kinases and involved in signaling for cell growth and c-myc induction. , 1997, Immunity.

[20]  T. Stevens,et al.  VPS27 controls vacuolar and endocytic traffic through a prevacuolar compartment in Saccharomyces cerevisiae , 1995, The Journal of cell biology.

[21]  E. Li,et al.  Smad2 role in mesoderm formation, left–right patterning and craniofacial development , 1998, Nature.

[22]  P. Hoodless,et al.  Smad2 Signaling in Extraembryonic Tissues Determines Anterior-Posterior Polarity of the Early Mouse Embryo , 1998, Cell.

[23]  N. Tanaka,et al.  Hrs Is Associated with STAM, a Signal-transducing Adaptor Molecule , 1997, The Journal of Biological Chemistry.

[24]  Rein Aasland,et al.  FYVE fingers bind PtdIns(3)P , 1998, Nature.

[25]  J. Rossant,et al.  The tumor suppressor gene Smad4/Dpc4 is required for gastrulation and later for anterior development of the mouse embryo. , 1998, Genes & development.

[26]  Rein Aasland,et al.  Endosomal Localization of the Autoantigen EEA1 Is Mediated by a Zinc-binding FYVE Finger* , 1996, The Journal of Biological Chemistry.

[27]  R. Behringer,et al.  Bmpr encodes a type I bone morphogenetic protein receptor that is essential for gastrulation during mouse embryogenesis. , 1995, Genes & development.

[28]  M. Komada,et al.  Hrs, a FYVE finger protein localized to early endosomes, is implicated in vesicular traffic and required for ventral folding morphogenesis. , 1999, Genes & development.

[29]  M. Khokha,et al.  Insertional mutation of a gene involved in growth regulation of the early mouse embryo , 1992, Developmental dynamics : an official publication of the American Association of Anatomists.

[30]  M. Komada,et al.  Hrs, a Tyrosine Kinase Substrate with a Conserved Double Zinc Finger Domain, Is Localized to the Cytoplasmic Surface of Early Endosomes* , 1997, The Journal of Biological Chemistry.

[31]  C. Deng,et al.  Failure of egg cylinder elongation and mesoderm induction in mouse embryos lacking the tumor suppressor smad2. , 1998, Proceedings of the National Academy of Sciences of the United States of America.