Skip to main content

Olfactomedin-like 2 A and B (OLFML2A and OLFML2B) profile expression in the retina of spotted gar (Lepisosteus oculatus) and bioinformatics mining

Abstract

Olfactomedin-like (OLFML) proteins are members of the olfactomedin domain–containing secreted glycoprotein (OLF) family. OLFML2A and OLFML2B are representative molecules of these glycoproteins. Olfactomedins are critical for the development and functional organization of the nervous system and retina, which is a highly conserved structure in vertebrates, having almost identical anatomical and physiological characteristics in multiple taxa. Spotted gar, a member of the Lepisosteidae family, is a freshwater fish that inhabits rivers, bayous, swamps, and brackish waters. Recently, the complete genome has been sequenced, providing a unique bridge between fish medical models to human biology, making it an excellent animal model. This study was aimed to understanding the evolution OLFML2A and OLFML2B in the retina of spotted gar through looking for the expression of these genes. Spotted gar retina was analyzed with hematoxylin-eosin staining assays to provide an overall view of the retina structure and an immunofluorescence assay to identify OLFML2A and OLFML2B protein expression. A phylogenetic tree was created using the neighbor-joining method. Forces that direct the evolution of the fish genes were tested. Spotted gar retina, as in other vertebrates, is made of several layers. OLFML2A and OLFML2B proteins were detected in the rod and cone photoreceptor layer (PRL), outer nuclear layer (ONL), and inner nuclear layer (INL). Phylogenetic tree analysis confirms the orthology within the OLFML2A gene. Purifying selection is the evolutionary force that directs the OLFML2A genes. OLFML2A genes have a well-conserved function over time and species.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

References

Download references

Acknowledgments

The authors gratefully acknowledge the critical reading of the manuscript by Sergio Lozano-Rodriguez.

Funding

The present work was supported by the grant number 16769 from the Mexican Council of Science and Technology, CONACYT.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Iram Pablo Rodriguez Sanchez.

Ethics declarations

The experimental protocol was reviewed and approved by the Research Ethics Committee of the Faculty of Biological Sciences (approval number FCB-CB-701).

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Garza-Rodríguez, M.L., González-Álvarez, R., Mendoza Alfaro, R.E. et al. Olfactomedin-like 2 A and B (OLFML2A and OLFML2B) profile expression in the retina of spotted gar (Lepisosteus oculatus) and bioinformatics mining. Fish Physiol Biochem 45, 1575–1587 (2019). https://doi.org/10.1007/s10695-019-00647-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10695-019-00647-0

Keywords

  • Spotted gar
  • Eye
  • Retina
  • Expression profile
  • Evolution
  • Olfactomedin