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The sagittal plane or lateral plane (longitudinal, anteroposterior) is a plane parallel to the sagittal suture. It divides the body into left and right. It divides the body into left and right. The coronal plane or frontal plane ( vertical ) divides the body into dorsal and ventral (back and front, or posterior and anterior) portions.
Signals that control anteroposterior neural development include FGF and retinoic acid, which act in the hindbrain and spinal cord. [16] The hindbrain, for example, is patterned by Hox genes , which are expressed in overlapping domains along the anteroposterior axis under the control of retinoic acid.
Drosophila melanogaster is an important model for understanding body plan generation and evolution. The general principles of Hox gene function and logic elucidated in flies will apply to all bilaterian organisms, including humans. Drosophila, like all insects, has eight Hox genes. These are clustered into two complexes, both of which are ...
Homeotic genes are genes which regulate the development of anatomical structures in various organisms such as echinoderms, [1] insects, mammals, and plants. Homeotic genes often encode transcription factor proteins, and these proteins affect development by regulating downstream gene networks involved in body patterning.
Many of the genes listed in Table 1 play an important role in embryonic development, specifically during skeletal patterning and limb bud formation. [18] The Shh gene, and genes belonging to the BMP, Hox, T-box, FGF, and Wnt families, all play a pivotal role in cell signaling and differentiation to regulate and promote successful limb formation ...
Patterning along the limb bud requires signals from many sources. Specifically, proteins called transcription factors (TF) help control the rate at which a gene is transcribed. The limb bud expresses a TF called ALX4 at the anterior part of the mesoderm, with the TF HOXB8 being expressed at the posterior portion. The Alx4 region, the medial ...
Different terms are used because of different body plans in animals, whether animals stand on one or two legs, and whether an animal is symmetrical or not, as discussed above. For example, as humans are approximately bilaterally symmetrical organisms, anatomical descriptions usually use the same terms as those for other vertebrates. [59]
Biological patterns such as animal markings, the segmentation of animals, and phyllotaxis are formed in different ways. [2]In developmental biology, pattern formation describes the mechanism by which initially equivalent cells in a developing tissue in an embryo assume complex forms and functions. [3]