Difference between revisions of "Developmental Signals - Pax"

From Embryology
Line 56: Line 56:
 
* craniofacial-deafness-hand syndrome (CDHS)
 
* craniofacial-deafness-hand syndrome (CDHS)
 
* rhabdomyosarcoma type 2 (RMS2)
 
* rhabdomyosarcoma type 2 (RMS2)
 +
 +
===Pax5===
 +
* acute lymphoblastic leukemia
  
 
==References==
 
==References==

Revision as of 11:24, 27 October 2010

Introduction

Phylogenetic tree of Pax genes[1]

The name derived from Drosophila gene "paired" (prd) with a box (homeodomain) domain. A transcription factor of the helix-turn-helix structural family, DNA binding, and activating gene expression. In human, there are nine member proteins from Pax1 to Pax9.

Pax6 has been identified as regulating development of the central nervous system, eyes, nose, pancreas and pituitary gland.

Factor Links: AMH | hCG | BMP | sonic hedgehog | bHLH | HOX | FGF | FOX | Hippo | LIM | Nanog | NGF | Nodal | Notch | PAX | retinoic acid | SIX | Slit2/Robo1 | SOX | TBX | TGF-beta | VEGF | WNT | Category:Molecular

Some Recent Findings

  • Downstream genes of Pax6 in the developing rat hindbrain [2] "These results indicate that Unc5h1 and Cyp26b1 are novel candidates for target genes transactivated by Pax6. Furthermore, our results suggest the interesting possibility that Pax6 regulates anterior-posterior patterning of the hindbrain via activation of Cyp26b1, an enzyme that metabolizes retinoic acid."

Functions

Neural

  • Hoxd4 gene a direct target of Pax6[3]
    • mouse embryo - Hoxd4 expression in rhombomere 7 and the spinal cord is reduced to some extent in the Pax6 mutant
    • zebrafish embryo - double knockdown of pax6a and pax6b with MOs resulted in malformed rhombomere boundaries and an anteriorized hoxd4a expression border
  • Pax3 is expressed in the somite, neural tube, and neural crest.
  • Pax3 is required for enteric ganglia formation.[4]
  • Pax2 and Pax5 in midbrain and cerebellum development.[5]

Vision

Pax6 eye phenotypes.jpg

Pax6 mutation eye phenotypes[6]

Pancreas

  • Pax6 acts in endocrine development in the pancreas as a glucagon gene transactivator role in alpha (α) cell development.
  • Pax2 is also expressed in the pancreas.
  • Pax4 is a regulator of pancreatic beta cell development.[7]

Thymus

Pax1 mouse KO thymus size reduction and impaired thymocyte maturation.

Structure

  • tissue-specific transcriptional regulators
  • contain a highly conserved DNA-binding domain with six alpha-helices (paired domain)
  • a complete or residual homeodomain.
  • 4 Groups: group I (Pax-1, 9), II (Pax-2, 5, 8), III (Pax-3, 7), and IV (Pax-4, 6)[8]


Abnormalities

Associated with defects in each Pax protein or their signaling pathway.

Pax3

  • Waardenburg syndrome type 1 (WS1)
  • Waardenburg syndrome type 3 (WS3)
  • craniofacial-deafness-hand syndrome (CDHS)
  • rhabdomyosarcoma type 2 (RMS2)

Pax5

  • acute lymphoblastic leukemia

References

  1. <pubmed>9144207</pubmed>
  2. <pubmed>20082710</pubmed>| BMC Dev. Biol.
  3. <pubmed>17010333</pubmed>
  4. <pubmed>11032856</pubmed>
  5. <pubmed>9405645</pubmed>
  6. <pubmed>19956802</pubmed>| PLoS Biol.
  7. <pubmed>15650323</pubmed>
  8. <pubmed>9254921</pubmed>

Search Bookshelf Pax

Reviews

<pubmed>17506689</pubmed> <pubmed>10197584</pubmed>

Search Pubmed

Search Pubmed Now: Pax

http://www.ncbi.nlm.nih.gov/omim

External Links

Glossary Links

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers | Symbols | Term Link

Cite this page: Hill, M.A. (2021, September 24) Embryology Developmental Signals - Pax. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Developmental_Signals_-_Pax

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© Dr Mark Hill 2021, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G