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Fig. 5
Blood-Flow-Independent Expression of klf2a/b mRNA in ccm2m201 Mutants
(A–C) The ccm2m201 mutant cardiac ballooning phenotype is flow independent. Frontal views of 48 hrpf hearts of the myocardial reporter line Tg(myl7:GFP)twu34 (Huang et al., 2003) show that cardiac expansion is not rescued in ccm2m201 mutant; tnnt2a morphants that lack blood flow.
(D) The expression levels of klf2a and klf2b mRNA, as measured by qRT-PCR, are elevated in ccm2m201 mutant; tnnt2a morphants that lack blood flow.
(E–G) Loss of Ccm2 results in overproliferation of the endocardium under no-flow conditions. (E) Quantifications of the ratio of proliferating versus nonproliferating endocardial cells between 33 and 53 hrpf in tnnt2a morphants compared with ccm2m201 mutant;tnnt2a morphants based on SPIM recordings (n = 2). (F) The endocardium of tnnt2a morphants is not proliferative as indicated by the lack of color-coded proliferative cells (still image derived from Movie S1, which is based on SPIM time-lapse recordings of endocardial morphogenesis marked by Tg(kdrl:GFP)s843 between 33 and53 hrpf). (G) The combined loss of Ccm2 and Tnnt2a is characterized by a high rate of proliferative events (indicated by uniquely colored daughter cells derived from proliferative events; still image derived from Movie S2). A, atrium; V, ventricle. Statistical data are means and SEM; ns, not significant; p < 0.05; p < 0.01; p < 0.001; p < 0.0001; see Supplemental Experimental Procedures for details about statistical data analysis.
Reprinted from Developmental Cell, 32, Renz, M., Otten, C., Faurobert, E., Rudolph, F., Zhu, Y., Boulday, G., Duchene, J., Mickoleit, M., Dietrich, A.C., Ramspacher, C., Steed, E., Manet-Dupé, S., Benz, A., Hassel, D., Vermot, J., Huisken, J., Tournier-Lasserve, E., Felbor, U., Sure, U., Albiges-Rizo, C., Abdelilah-Seyfried, S., Regulation of β1 Integrin-Klf2-Mediated Angiogenesis by CCM Proteins, 181-190, Copyright (2015) with permission from Elsevier. Full text @ Dev. Cell