Analyses of clones can also provide information about cell death and proliferation, cell competition, cell movement and dispersion, and tissue polarity. Clonal analyses, which describe the derivatives of a single cell, provide insight into the mode of growth of a tissue and its regionalization with potential clonal boundaries (Garcia-Bellido et al., 1973) between compartments, or with segregation between distinct cell lineages, which do not necessarily correspond to distinct differentiated cell types but rather to topographical subdivisions (Lescroart et al., 2010). These interrogations now extend to the origin of stem cells that permit the regeneration of an adult structure as well as its initial formation. Lineage studies, then as now, aim to establish which cells, and how many cells, in the early embryo will give rise to a structure and, as development proceeds, from which part of a structure a substructure derives.
Many of the conceptual issues of today were evident when cell lineages were first explored.
Morgan and others on spontaneously generated mosaicism in insects, led to retrospective analyses in which cell lineage and gene function were associated (Sturtevant, 1929). Sturtevant, based on genetic studies initiated by T.H. In addition to embryological approaches, the work of A.H. Breakthroughs in vertebrate fate mapping came from the systematic use of vital staining of groups of cells (Vogt, 1929) and from grafting experiments (Spemann and Mangold, 1924) in the amphibian embryo. Conklin (1905), another major figure, made the distinction between determinate and indeterminate types of cleavage in ascidians, leading to the concept of invariant and noninvariant cell lineages. Wilson viewed lineage in terms of the fate of cells and E.G. Before the end of the 19th century, the work of Charles Whitman (1887) and later of Edmund Wilson (1892) on leech and annelid embryos led to the formulation of the term ‘‘cell lineage.’’ This early work inspired the Wood’s Hole School at the Marine Biology Laboratory in Massachusetts, where pioneering research in invertebrate embryos led to important concepts for lineage analysis. In the mid-19th century, identification of cells as the basic units of life (Schleiden, 1838 Schwann, 1839) led to the realization that cells come from pre-existing cells (Virchow, 1858). History and Concepts Cell lineage analysis is intimately connected with the emergence of developmental biology as a field of scientific research (see Galperin, 1998). Technological advances in genetically engineered permanent cell labeling, together with a multiplicity of fluorescent markers and sophisticated imaging, open new possibilities for prospective and retrospective clonal analysis. Reconstructing the lineage of cells is central to understanding development and is now also an important issue in stem cell research. Meilhac1,* 1Molecular Genetics of Development Unit, CNRS URA 2578, Department of Developmental Biology, Institut Pasteur, 28 rue du Dr Roux, 75015 Paris, France *Correspondence: (M.E.B.), (S.M.M.) DOI 10.1016/j.devcel.2011.07.019 Perspective Tracing Cells for Tracking Cell Lineage and Clonal Behavior Margaret E.
0 kommentar(er)
