Summary
The role of actin bundles on the heart looping of chick embryos was examined by using cytochalasin B, which binds to the barbed end of actin filaments and inhibits association of the subunits. It was applied to embryos cultured according to New's method. Looping did not occur when cytochalasin B was applied diffusely in the medium. Further, we disorganized actin bundles in a limited part of the heart tube to examine the role of actin bundles in each part in asymmetry formation. A small crystal of cytochalasin B was applied to the caudal part of the heart tube on either the left or right side. The disorganization of actin bundles on the left side resulted in the right-bending of the heart, an initial sign of dextro-looping (normal pattern), and right side disorganization resulted in left-bending. We suggest that actin bundles on the right side of the caudal part of a heart tube generate tension and cause dextro-looping. Embryos whose hearts bent to the right rotated their heads to the right, and embryos with left-bent-hearts rotated their heads to the left. The rotation of the heart tube may therefore decide in which direction the body axis rotates.
Similar content being viewed by others
References
Alberts B, Bray D, Lewis J, Raff M, Roberts K, Watson JD (eds) (1989) Molecular biology of the cell, 2nd edn. Garland Publishing, New York London, pp 613–680
Afzelius BA (1985) The immotile-cilia syndrome: a microtubuleassociated defect. CRC Crit Rev Biochem 19:63–87
Brown NA, Wolpert L (1990) The development of handedness in left/right asymmetry. Development 109:1–9
Cooper JA (1987) Effects of cytochalasin and phalloidin on actin. J Cell Biol 105:1473–1478
Galloway J (1990) A handle on handedness. Nature 346:223–224
Ghaskadbi S, Mulherkar L (1984) Effects of cytochalasin H on chick embryo explants cultured in vitro. Toxicology 33:323–330
Hamburger V, Hamilton HL (1951) A series of normal stages in the development of the chick embryo. J Morphol 88:49–92
Handel MA, Kennedy JR (1984) Situs inversus in homozygous mice without immotile cilia. J Hered 75:498
Hiruma T, Hirakow R (1985) An ultrastructural topographical study on myofibrillogenesis in the heart of the chick embryo during pulsation onset period. Anat Embryol 172:325–329
Itasaki N, Nakamura H, Yasuda M (1989) Changes in the arrangement of actin bundles during heart looping in the chick embryo. Anat Embryol 180:413–420
Karfunkel P (1972) The activity of microtubules and microfilaments in neurulation in the chick. J Exp Zool 181:289–302
Lepori NG (1967) Research on heart development in chick embryo under normal and experimental conditions. Monit Zool Ital 1:159–183
Manasek FJ (1972) The sensitivity of developing cardiac myofibrils to cytochalasin-B. Proc Natl Acad Sci USA 69:308–312
Manasek FJ (1976) Heart development: interactions involved in cardiac morphogenesis. In: Poste G, Nicolson GL (eds) The cell surface in animal embryogenesis and development. Elsevier/North Holland Biochemical Press, New York, pp 545–598
Manasek FJ (1981) Determinants of heart shape in early embryos. Fed Proc 40:2011–2016
Manasek FJ, Isobe Y, Shimada Y, Hopkins W (1984) The embryonic myocardial cytoskeleton, interstitial pressure, and the control of morphogenesis. In: Nora JJ, Takao A (eds) Congenital heart disease: cause and processes. Futura Publishing Co, Mount Kisco, New York, pp 359–376
New DAT (1955) A new technique for the cultivation of the chick embryo in vitro. J Embryol Exp Morph 3:320–331
Odell GM, Oster G, Alberch P, Burnside B (1981) The mechanical basis of morphogenesis. 1. Epithelial folding and invagination. Dev Biol 85:446–462
Ostrovsky D, Sanger JW, Lash JW (1983) Light microscope observations on actin distribution during morphogenetic movements in the chick embryo. J Embryol Exp Morphol 78:23–32
Sato M, Schwarz WH, Pollard TD (1987) Dependence of the mechanical properties of actin/α-actinin gels on deformation rate. Nature 325:828–830
Stalsberg H (1969) The origin of heart asymmetry: right and left contributions to the early chick embryo heart. Dev Biol 19:109–127
Stalsberg H (1970) Mechanism of dextral looping of the embryonic heart. Am J Cardiol 25:265–271
Witschi E (1956) Development of vertebrates. WB Saunders Company, Philadelphia, pp 259–267
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Itasaki, N., Nakamura, H., Sumida, H. et al. Actin bundles on the right side in the caudal part of the heart tube play a role in dextro-looping in the embryonic chick heart. Anat Embryol 183, 29–39 (1991). https://doi.org/10.1007/BF00185832
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00185832