CCM3 signaling through sterile 20-like kinases plays an essential role during zebrafish cardiovascular development and cerebral cavernous malformations.
Cerebral cavernous malformation is a common human vascular disease that arises due to loss-of-function mutations in genes encoding three intracellular adaptor proteins, cerebral cavernous malformations 1 protein (CCM1), CCM2, and CCM3. CCM1, CCM2, and CCM3 interact biochemically in a pathway required in endothelial cells during cardiovascular development in mice and zebrafish. The downstream effectors by which this signaling pathway regulates endothelial function have not yet been identified. Here we have shown in zebrafish that expression of mutant ccm3 proteins (ccm3Delta) known to cause cerebral cavernous malformation in humans confers cardiovascular phenotypes identical to those associated with loss of ccm1 and ccm2. CCM3Delta proteins interacted with CCM1 and CCM2, but not with other proteins known to bind wild-type CCM3, serine/threonine protein kinase MST4 (MST4), sterile 20-like serine/threonine kinase 24 (STK24), and STK25, all of which have poorly defined biological functions. Cardiovascular phenotypes characteristic of CCM deficiency arose due to stk deficiency and combined low-level deficiency of stks and ccm3 in zebrafish embryos. In cultured human endothelial cells, CCM3 and STK25 regulated barrier function in a manner similar to CCM2, and STKs negatively regulated Rho by directly activating moesin. These studies identify STKs as essential downstream effectors of CCM signaling in development and disease that may regulate both endothelial and epithelial cell junctions.
Zheng
Xiangjian
X
Department of Medicine and Cardiovascular Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Xu
Chong
C
Di Lorenzo
Annarita
A
Kleaveland
Benjamin
B
Zou
Zhiying
Z
Seiler
Christoph
C
Chen
Mei
M
Cheng
Lan
L
Xiao
Jiping
J
He
Jie
J
Pack
Michael A
MA
Sessa
William C
WC
Kahn
Mark L
ML
D000595:Amino Acid Sequence; D000818:Animals; D051017:Apoptosis Regulatory Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D002319:Cardiovascular System / Q000196:embryology*; D017124:Conserved Sequence; D020786:Hemangioma, Cavernous, Central Nervous System / Q000209:etiology*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000502:physiology*; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D008840:Microfilament Proteins / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000502:physiology; D008969:Molecular Sequence Data; D009124:Muscle Proteins; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D016415:Sequence Alignment; D015398:Signal Transduction / Q000502:physiology*; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D000099317:Hippo Kinases
D051017:Apoptosis Regulatory Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D008840:Microfilament Proteins; D008869:Microtubule-Associated Proteins; D009124:Muscle Proteins; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D029961:Zebrafish Proteins; C495390:PDCD10 protein, human; C514537:krit1 protein, zebrafish; C542753:pdcd10a protein, zebrafish; C071058:moesin; C530660:STK25 protein, human; D000099317:Hippo Kinases