Disease relevance of Acvr1b

• Seminomas expressed significantly lower levels of ActRIIA (P<0.05, Mann-Whitney U-test) and higher levels of ActRIA (P<0.05) and ActRIB (P<0.05) compared with non-seminomas [1].

High impact information on Acvr1b

• ActRIB is a type I transmembrane serine/threonine kinase receptor that has been shown to form heteromeric complexes with the type II activin receptors to mediate activin signal [2].
• To assess the function of ActRIB in mesoderm formation and gastrulation, chimera analysis was conducted [2].
• To investigate the function of ActRIB in mammalian development, we generated ActRIB-deficient ES cell lines and mice by gene targeting [2].
• Primitive streak formation, however, was impaired in chimeras when ActRIB-/- cells contributed highly to the epiblast [2].
• Analysis of the ActRIB-/- embryos showed that the epiblast and the extraembryonic ectoderm were disorganized, resulting in disruption and developmental arrest of the egg cylinder before gastrulation [2].

Biological context of Acvr1b

• In contrast, HS-72 clones that over-expressed ActRIB significantly facilitated activin A-induced apoptosis [3].

Anatomical context of Acvr1b

• Conversely, only ActR-IB mRNA is detected in the olfactory region, eye, tooth primordium, esophagus, mesonephros, dorsal root ganglia and is strongly expressed in the spinal cord [4].
• ActR-I mRNA, but not ActR-IB, is expressed in blood vessels, the heart, tongue, intervertebral discs and diaphragm [4].
• We found that ActRIB-/- ES cells injected into wild-type blastocysts were able to contribute to the mesoderm in chimeric embryos, suggesting that ActRIB is not required for mesoderm formation [2].

Physical interactions of Acvr1b

• We describe the cDNA cloning of the mouse homologue of human ActR-IB and analyze binding of radio-iodinated activin on type I/type II combinations of mouse receptors expressed from cDNA [4].

Other interactions of Acvr1b

• In the presence of Smad7, overexpression of an activated form of ActR-IB, but not of an activated form of ActR-I, induced F5-5 cells to differentiate [5].
• The type I activin receptor ActRIB is required for egg cylinder organization and gastrulation in the mouse [2].

Analytical, diagnostic and therapeutic context of Acvr1b

• We studied the distribution of ActR-I and ActR-IB mRNAs in postimplantation mouse embryos by in situ hybridization [4].

References