Sevenless

Last updated
Sevenless
Identifiers
Organism Drosophila melanogaster
Symbolsev
UniProt P13368
Search for
Structures Swiss-model
Domains InterPro

Sevenless (sev) is a gene in the fruit fly Drosophila melanogaster that encodes a receptor tyrosine kinase protein essential to the development of the R7 photoreceptor cells in the Drosophila embryonic eye. [1] The Drosophila ommatidium contains 8 distinct retinula or R cells, each of which has a different spectral sensitivity. The R7 photo receptor, located in each of several ommatidia in the fly's compound eye, is used to detect ultraviolet light. [2] The R8 photoreceptor contains an activator of the RTK (receptor tyrosine kinase) for on a precursor R7 cell, called the bride of sevenless (BOSS). The binding of BOSS to sevenless stimulates a complex series of reactions involving the RTK (sevenless), MAP kinases, Ras and many more molecules to differentiate that precursor R7 photo receptor to a fully functional R7 photo receptor that can see UV light. Much of this knowledge was gained by examining flies with a mutant sevenless which still produced a fully functional R7 photoreceptor when a dominant Ras was injected into the mutant R7 precursor.

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References

  1. Darnell J, Baltimore D, Matsudaira P, Zipursky SL, Berk A, Lodish H (10 June 2019). "Receptor Tyrosine Kinases and Ras". Molecular Cell Biology. 4th Edition via www.ncbi.nlm.nih.gov.
  2. Smith CU (2002) [1989]. "19.5 Morphogenesis in the Drosophila eye". Elements of Molecular Neurobiology. Oxford Journals. pp. 450–451. ISBN   0-471-56038-3.