Biomedical Engineering Reference
In-Depth Information
3.1
DEVELOPMENTAL BIOLOGY:
BRANCHING MORPHOGENESIS
S.R. Lubkin
Department of Mathematics,
North Carolina State University, Raleigh
Branching morphogenesis is a ubiquitous system in the developmental biology of macro-
scopic organisms. Many of the details are known, yet a unified understanding remains out
of reach. Many of the relevant facts about branching morphogenesis become clearer if we
include a mechanical interpretation of the interactions between tissues.
1.
INTRODUCTION
Lewis Wolpert (63) has often said that "gastrulation is the most important
event in your life," but it is not the most frequent phenomenon in the develop-
ment of an organism. Gastrulation occurs just once, but branching morphogene-
sis happens early and often. The formation of branched tubular structures-
glands-occurs throughout an organism, in many different tissues, and is essen-
tial to the existence of virtually all organisms which need to transport fluids
more than about a millimeter.
If you are macroscopic, you need ducts. How do they form?
Branching morphogenesis is widespread in animal development, generating
the form of such diverse organs as the lung, pancreas, mammary gland, salivary
Address correspondence to: S.R. Lubkin, Department of Mathematics, Box 8203, North Carolina
State University, Raleigh, NC 27695-8205 (lubkin@eos.ncsu.edu); North Carolina State University,
Raleigh, NC 27695-8205.
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