Achaete-scute complex

Last updated
Achaete-scute-related
Identifiers
SymbolMASH1/Ascl1a-like
InterPro IPR015660
Achaete-scute complex protein T5
Identifiers
Organism Drosophila melanogaster
Symbolac
UniProt P10083
Search for
Structures Swiss-model
Domains InterPro
Achaete-scute complex protein T4
Identifiers
Organism Drosophila melanogaster
Symbolsc
UniProt P10084
Search for
Structures Swiss-model
Domains InterPro
Achaete-scute complex protein T3
Identifiers
Organism Drosophila melanogaster
Symboll(1)sc
UniProt P09774
Search for
Structures Swiss-model
Domains InterPro
Achaete-scute complex protein T8
Identifiers
Organism Drosophila melanogaster
Symbolase
UniProt P09775
Search for
Structures Swiss-model
Domains InterPro

The achaete-scute complex (AS-C) is a group of four genes (achaete, scute, lethal of scute, and asense) in the fruit fly Drosophila melanogaster . These genes encode basic helix-loop-helix transcription factors that have been best studied in their regulation of nervous system development. [1] [2] Because of their role in specifying neuroblast fate, the genes of the AS-C are called proneural genes. However, the AS-C has non-proneural functions, such as specifying muscle and gut progenitors. [1] Homologues of AS-C in other animals, including humans and other vertebrates, have similar functions.

Contents

Genes of the AS-C interact with the Notch pathway in both their proneural functions as well as their specification of gut and muscle cells. [1]

Genetic structure

The complex is found near the tip of the X chromosome, just 3' of yellow, in chromosome bands 1A6 through 1B3. It occupies around 93 kb of the genome, with all four genes oriented in the same direction.

achaete

The 5′-most gene of the achaete-scute complex, achaete (short form ac), is a small gene of less than 1000 bp. The Achaete protein is 201 amino acids long and has a relative size of 23 kDa. [3] As with most classically described Drosophila genes, achaete is named for its mutant phenotype, which is the lack of sensory hairs (macrochaetae and microchaetae) on the back of the adult fly. Achaete functions to specify sensory hair cell fate. It functions downstream of other genes, including hairy and extramacrochaete, that set up fields of cells that may express achaete.

scute

Scute (short form sc) is found in about 25 kb (3)′ of achaete. It is a 1.45 kb gene encoding a 345 aa protein of 38.2 kDa. [4]

lethal or scute

lethal or scute (short form l(1)sc) is found about 12 kb 3′ of scute. It is a 1.1 kb gene encoding a 257 aa protein of 29 kDa. [5]

asense

asense (short form ase) found 45 kb 3′ of l(1)sc. It is a 2.8 kb gene encoding a 486 aa protein of 53.2 kDa. [6]

See also

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Proneural genes encode transcription factors of the basic helix-loop-helix (bHLH) class which are responsible for the development of neuroectodermal progenitor cells. Proneural genes have multiple functions in neural development. They integrate positional information and contribute to the specification of progenitor-cell identity. From the same ectodermal cell types, neural or epidermal cells can develop based on interactions between proneural and neurogenic genes. Neurogenic genes are so called because loss of function mutants show an increase number of developed neural precursors. On the other hand, proneural genes mutants fail to develop neural precursor cells.

María Domínguez Castellano is a Spanish neuroscientist and director of the Department of Developmental Neurobiology in the Institute of Neurosciences, Alicante, Spain, which is a joint Miguel Hernández University of Elche (UMH) and Spanish National Research Council (CSIC) institution.

References

  1. 1 2 3 García-Bellido A, de Celis JF (July 2009). "The complex tale of the achaete-scute complex: a paradigmatic case in the analysis of gene organization and function during development". Genetics. 182 (3): 631–9. doi:10.1534/genetics.109.104083. PMC   2710146 . PMID   19622761.
  2. "Achaete-scute complex" . Retrieved 2009-11-29.
  3. "FlyBase achaete report" . Retrieved 2009-11-29.
  4. "FlyBase scute report" . Retrieved 2009-11-29.
  5. "FlyBase lethal of scute report" . Retrieved 2009-11-29.
  6. "FlyBase asense report" . Retrieved 2009-11-29.