Controlling development by the numbers

30 Wednesday Oct 2013

Posted by sedeer in Development, Genetics, Vertebrates

Tags

animals, backbone, biology, Developmental biology, Gene, Gene expression, notochord, Popular science, science

Genes have to be carefully coordinated to switch on at just the right moment in development in order to make a mature, complex embryo out of just a single cell. Scientists working at the Weill Medical College of Cornell University in New York have discovered how this coordination is accomplished. In a paper just published in PLOS Biology, they describe how the gene Brachyury controls the timing of a cascade of genes involved in a crucial process in vertebrate development. Continue reading →

Telling left from right: which side gets the heart?

23 Tuesday Oct 2012

Posted by sedeer in Development, Evolution, Form, Genetics, Vertebrates

≈ 3 Comments

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animals, biology, Cytoskeleton, emergence, Popular science, science, shape, symmetry, Tubulin

This was originally a guest post on The Trenches of Discovery. Thanks, Shaun!

One out of every 8,000 humans is born with some of their internal organs on the wrong side of their body, a condition which can have serious medical consequences. Although we’re usually described as symmetric, that’s only superficially true. Like other vertebrates, we look symmetric from the outside but our internal organs show left-right asymmetry; unless you happen to be a Time Lord, you have only one heart which is normally located on the left side of your chest. Changes to the organization of the internal organs can lead to cardiac defects, misalignment of the bowel and other serious problems. Many genes are known to play a role in establishing this asymmetry, but we still don’t fully understand its evolutionary and developmental origins. Earlier this year, a paper published in the journal PNAS described how this asymmetry is established by subcellular components early in embryonic development.

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Head to tail: segmenting the body

12 Sunday Feb 2012

Posted by sedeer in Development, Vertebrates

≈ 1 Comment

Tags

animals, biology, clock and wavefront, Developmental biology, embryo, Embryogenesis, Popular science, science, somitogenesis

Unlike plants, which can continue to develop new organs and elaborate their body plan throughout their life, animals generally have to contend with a body plan which is fixed at birth. The basic body plan is laid out during embryogenesis, the intricately choreographed interplay of different processes and mechanisms involved in the development of the embryo. An important step early in animal embryogenesis is the lengthwise division of the embryo into a series of primitive segments, called somites; each somite will later give rise to vertebrae, skeletal muscle, and dermis, although some of the somites may fuse before this happens. Correct formation of the somites is a crucial component of the development and is precisely regulated in both space and time. This tight regulation is accomplished by a remarkably simple, beautiful and ancient mechanism.