A homeobox is a DNA sequence, around 180 base pairs long, that regulates large-scale anatomical features in the early stages of embryonic development. Mutations in a homeobox may change large-scale anatomical features of the full-grown organism.
In evolutionary developmental biology, homeosis is the transformation of one organ into another, arising from mutation in or misexpression of certain developmentally critical genes, specifically homeotic genes. In animals, these developmental genes specifically control the development of organs on their anteroposterior axis. In plants, however, the developmental genes affected by homeosis may control anything from the development of a stamen or petals to the development of chlorophyll. Homeosis may be caused by mutations in Hox genes, found in animals, or others such as the MADS-box family in plants. Homeosis is a characteristic that has helped insects become as successful and diverse as they are.
Eric Francis Wieschaus is an American evolutionary developmental biologist and 1995 Nobel Prize-winner.
Alfred Henry Sturtevant was an American geneticist. Sturtevant constructed the first genetic map of a chromosome in 1911. Throughout his career he worked on the organism Drosophila melanogaster with Thomas Hunt Morgan. By watching the development of flies in which the earliest cell division produced two different genomes, he measured the embryonic distance between organs in a unit which is called the sturt in his honor. On February 13, 1968, Sturtevant received the 1967 National Medal of Science from President Lyndon B. Johnson.
Michael Ashburner was an English biologist and Professor in the Department of Genetics at University of Cambridge. He was also the former joint-head and co-founder of the European Bioinformatics Institute (EBI) of the European Molecular Biology Laboratory (EMBL) and a Fellow of Churchill College, Cambridge.
Hox genes, a subset of homeobox genes, are a group of related genes that specify regions of the body plan of an embryo along the head-tail axis of animals. Hox proteins encode and specify the characteristics of 'position', ensuring that the correct structures form in the correct places of the body. For example, Hox genes in insects specify which appendages form on a segment, and Hox genes in vertebrates specify the types and shape of vertebrae that will form. In segmented animals, Hox proteins thus confer segmental or positional identity, but do not form the actual segments themselves.
Polycomb-group proteins are a family of protein complexes first discovered in fruit flies that can remodel chromatin such that epigenetic silencing of genes takes place. Polycomb-group proteins are well known for silencing Hox genes through modulation of chromatin structure during embryonic development in fruit flies. They derive their name from the fact that the first sign of a decrease in PcG function is often a homeotic transformation of posterior legs towards anterior legs, which have a characteristic comb-like set of bristles.
Gerald Mayer Rubin is an American biologist, notable for pioneering the use of transposable P elements in genetics, and for leading the public project to sequence the Drosophila melanogaster genome. Related to his genomics work, Rubin's lab is notable for development of genetic and genomics tools and studies of signal transduction and gene regulation. Rubin also serves as a vice president of the Howard Hughes Medical Institute and executive director of the Janelia Research Campus.
Homeobox protein Hox-B5 is a protein that in humans is encoded by the HOXB5 gene.
Homeotic genes are genes which regulate the development of anatomical structures in various organisms such as echinoderms, 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.
The Bithorax complex (BX-C) is one of two Drosophila melanogaster homeotic gene complexes, located on the right arm of chromosome 3. It is responsible for the differentiation of the posterior two-thirds of the fly by the regulation of three genes within the complex: Ultrabithorax (Ubx), abdominal A (abd-A), and Abdominal B (Abd-B).
Allan C. Spradling is an American scientist and principal investigator at the Carnegie Institution for Science and the Howard Hughes Medical Institute who studies egg development in the model organism, Drosophila melanogaster, a fruit fly. He is considered a leading researcher in the developmental genetics of the fruit fly egg and has developed a number of techniques in his career that have led to greater understanding of fruit fly genetics including contributions to sequencing its genome. He is also an adjunct professor at Johns Hopkins University and at the Johns Hopkins University School of Medicine.
Homeotic selector genes confer segment identity in Drosophila. They encode homeodomain proteins which interact with Hox and other homeotic genes to initiate segment-specific gene regulation. Homeodomain proteins are transcription factors that share a DNA-binding domain called the homeodomain. Changes in the expression and function of homeotic genes are responsible for the changes in the morphology of the limbs of arthropods as well as in the axial skeletons of vertebrates. Mutations in homeotic selector genes do not lead to elimination of a segment or pattern, but instead cause the segment to develop incorrectly.
Zerknüllt is a gene in the Antennapedia complex of Drosophila and other insects, where it operates very differently from the canonical Hox genes in the same gene cluster. Comparison of Hox genes between species showed that the Zerknüllt gene evolved from one of the standard Hox genes in insects through accumulating many amino acid changes, changing expression pattern, losing ancestral function and gaining a new function.
Michael Levine is an American developmental and cell biologist at Princeton University, where he is the Director of the Lewis-Sigler Institute for Integrative Genomics and a Professor of Molecular Biology.
Norbert Perrimon is a French geneticist and developmental biologist. He is the James Stillman Professor of Developmental Biology in the Department of Genetics at Harvard Medical School, an Investigator at the Howard Hughes Medical Institute, and an Associate of the Broad Institute. He is known for developing a number of techniques for used in genetic research with Drosophila melanogaster, as well as specific substantive contributions to signal transduction, developmental biology and physiology.
Lingadahalli Subrahmanya Shashidhara, currently the Centre Director of National Centre for Biological Sciences, Bengaluru, India, is an Indian developmental biologist, geneticist and a professor of biology. He is a Professor at the Indian Institute of Science Education and Research, Pune, and at Ashoka University, Sonepat, India.[3]. He heads the LSS Laboratory at IISER and is known for his studies on Drosophila, particularly Evolution of appendages and functions of homeotic selector genes. He is a J. C. Bose National Fellow of the Department of Science and Technology and an elected fellow of the Indian National Science Academy, Indian Academy of Sciences and the National Academy of Sciences, India. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards, in 2008, for his contributions to biological sciences.
Reinhard F. Stocker is a Swiss biologist. He pioneered the analysis of the sense of smell and taste in higher animals, using the fly Drosophila melanogaster as a study case. He provided a detailed account of the anatomy and development of the olfactory system, in particular across metamorphosis, for which he received the Théodore-Ott-Prize of the Swiss Academy of Medical Sciences in 2007, and pioneered the use of larval Drosophila for the brain and behavioural sciences.
Anthony Mahowald is a molecular genetics and cellular biologist who served as the department chair of the molecular genetics and cellular biology department at the University of Chicago. His lab focused on the Drosophila melanogaster, which is often referred to as fruit fly, specifically focusing on controlling the genetic aspect of major developmental events. His major research breakthroughs included the study of the stem cell niche, endocycles, and various types of actin.
