Headless flies produced by mutations in the paralogousPax6geneseyelessandtwin of eyeless

Kronhamn, Jesper; Frei, Erich; Daube, Michael; Jiao, Renjie; Shi, Yandong; Noll, Markus; Rasmuson-Lestander, Åsa

doi:10.1242/dev.129.4.1015

Cited by 70 publications

(5 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similarly, the vast majority of toy hdl and toy 1 null mutants also lack the eye-antennal disks [154,155]. However, a small number of both mutant alleles do survive to adulthood and have ocellar defects [132,152,155,156]. This is consistent with the loss of ocelli that is seen when toy is knocked down via RNAi just within the ocellar domain (Fig.…”

Section: Development Of the Ocellar Domainsupporting

confidence: 67%

“…When expression of both genes is simultaneously knocked down (to eliminate all Pax6 function), the eye-antennal disks fail to form and the resulting pharate adults are headless [154]. Similarly, the vast majority of toy hdl and toy 1 null mutants also lack the eye-antennal disks [154,155]. However, a small number of both mutant alleles do survive to adulthood and have ocellar defects [132,152,155,156].…”

Section: Development Of the Ocellar Domainmentioning

confidence: 99%

See 1 more Smart Citation

Development of the ocellar visual system in Drosophila melanogaster

Jean‐Guillaume

Kumar

2022

The FEBS Journal

View full text Add to dashboard Cite

The adult visual system of the fruit fly, Drosophila melanogaster, contains seven eyes-two compound eyes, a pair of Hofbauer-Buchner eyelets, and three ocelli. Each of these eye types has a specialized and essential role to play in visual and/or circadian behavior. As such, understanding how each is specified, patterned, and wired is of primary importance to vision biologists. Since the fruit fly is amenable to manipulation by an enormous array of genetic and molecular tools, its development is one of the best and most studied model systems. After more than a century of experimental investigations, our understanding of how each eye type is specified and patterned is grossly uneven. The compound eye has been the subject of several thousand studies; thus, our knowledge of its development is the deepest. By comparison, very little is known about the specification and patterning of the other two visual systems. In this Viewpoint article, we will describe what is known about the function and development of the Drosophila ocelli.

show abstract

Section: Development Of the Ocellar Domainsupporting

confidence: 67%

Section: Development Of the Ocellar Domainmentioning

confidence: 99%

Development of the ocellar visual system in Drosophila melanogaster

Jean‐Guillaume

Kumar

2022

The FEBS Journal

View full text Add to dashboard Cite

show abstract

“…In a limited capacity, researchers have focused on the compound eyes of insects such as Drosophila, and there are few molecular studies on the development of compound eyes of crustaceans. It has been discovered that loss of ey is linked to the headless phenotype in Drosophila, while toy acts upstream of ey and activates its expression [56][57][58][59][60]. In this study, the key genes in retinal determination network have been identified in the deep-sea and shallow-water shrimps, and two 'master regulator' Pax6 paralogs, ey and toy, are present in the two species.…”

Section: Discussionmentioning

confidence: 91%

Characterization and Comparison of Eye Development and Phototransduction Genes in Deep- and Shallow-Water Shrimp Alvinocaris longirostris and Palaemon carinicauda

et al. 2022

View full text Add to dashboard Cite

The investigations of the molecular components of eye development and phototransduction in deep-sea species are important to elucidate the mechanism of their adaptation to dim light. In this study, eye transcriptomes of the shrimp Alvinocaris longirostris from the deep-sea chemosynthetic ecosystem and the shallow-water shrimp Palaemon carinicauda were compared. Two Pax6 homologs with low expression levels were identified in both species, which are essential transcription factors in eye development. This finding implies that the development of the two shrimp eyes at early embryo–larvae stages might be similar. The multiple components of the phototransduction pathway were identified in both species. However, the number of phototransduction components was significantly reduced in A. longirostris, as well as expression level. Particularly, short-wavelength/UV-sensitive (SWS/UVS) opsins were absent in A. longirostris and only one putative middle-wavelength-sensitive (MWS) opsin was identified in this species. The conserved sites and structures of the putative LWS opsins were found between deep-sea and shallow-water decapods, indicating that the opsins in deep-sea crustaceans may also conserve their spectral absorption and signal transduction function. Phylogenetic analyses supported the monophyly of LWS opsins and SWS/UVS opsins in arthropods, while the MWS clade fell outside of the main arthropod LWS clade. The results are expected to provide baseline for study of visual adaptation in deep-sea shrimps.

show abstract

“…Successful execution of these pivotal functions depends on precisely regulated expression in time and tissue context. A systematic analysis in Drosophila demonstrated the critical effects of these variables as the misexpression of Pax genes leads to dramatic morphological phenotypes in the developing head [37]. In the specific case of the arthropod Pax transcription factor paralogs ey and toy, these aspects are highlighted by the extreme nature of lack of function and gene misexpression consequences.…”

Section: Discussionmentioning

confidence: 99%

Evolutionary Conservation of Five Pax6 Homologs under Strong Purifying Selection in the Horseshoe Crab Species Cluster

Dakarapu,

Friedrich

2023

Preprint

View full text Add to dashboard Cite

Horseshoe crabs represent the most ancestral chelicerate lineage characterized by marine ecology and the possession of lateral compound eyes. While considered living fossils, recent studies reported an unusual number of Pax6 transcription factor genes in the Atlantic horseshoe crab Limulus polyphemus. Pax genes encode a family of ancient metazoan transcription factors, which comprise seven subfamilies. Among these, the members of the Pax6 subfamily confer critical functions in the development of the head, the visual system, and further body plan components. Arthropods are characterized by two Pax6 subfamily homologs that were discovered in Drosophila and named eyeless (ey) and twin of eyeless (toy). However, whole genome sequence searches uncovered three homologs of ey and two homologs of toy in L. polyphemus. These numbers are explained by the occurrence of three whole genome duplications (WGD) in the lineage to the last common ancestor of L. polyphemus and its closely related three additional members of the extant horseshoe crab species cluster. Here we report comparative sequence evidence for the functional conservation of the five L. polyphemus Pax6 transcription factor homologs. Our analyses reveal that all paralogs are conserved in the approximately 135 million-year-old horseshoe crab species cluster and that they evolve under strong purifying selection. These findings identify subfunctionalization as the likeliest post-WGD outcome for the five Pax6 homologs. While awaiting confirmation by gene expression studies, this scenario would reconcile the discrepancy between the WGD-expanded gene repertoires and phenotypic stasis in the horseshoe crabs.

show abstract

Headless flies produced by mutations in the paralogousPax6geneseyelessandtwin of eyeless

Cited by 70 publications

References 27 publications

Development of the ocellar visual system in Drosophila melanogaster

Development of the ocellar visual system in Drosophila melanogaster

Characterization and Comparison of Eye Development and Phototransduction Genes in Deep- and Shallow-Water Shrimp Alvinocaris longirostris and Palaemon carinicauda

Evolutionary Conservation of Five Pax6 Homologs under Strong Purifying Selection in the Horseshoe Crab Species Cluster

Contact Info

Product

Resources

About