SEMINAR: MBF 602 Seminar- Benjamin Mason Friday, February 26th, 2010 4:00pm S/A seminar room

[Cary Rios <crios@rsmas.miami.edu>]

Stoplights on the reef: The molecular physiology and ecology of photoreception in coral larvae

 

 

Abstract

Photosensitive behaviors and circadian rhythms are well documented in reef-building corals and their larvae, yet the ecological role that photoreception plays in larval navigation and substrate recognition is poorly understood.  While waterborne and membrane-bound chemical cues are known to influence larval settlement and metamorphosis, I provide evidence that color may also play a role. Settlement experiments with Porites astreoides and Acropora palmata demonstrate that larvae settle and metamorphose at a greater frequency on red/orange substrates than on other colors. Electroretinographic traces confirm an opsin-like photosensitive response and indicate that the spectral sensitivity peaks of coral photoreceptors are shifted towards the orange-red region of the visible light spectrum, similar to the spectral emission of preferred artificial (plastic) and natural (crustose coralline algae) settlement substrates. Using Blast analyses and a PCR-based approach, I have identified, sequenced and cloned two full-length opsin cDNAs from A. palmata.  I have also identified and amplified partial opsin cDNAs from Montastrea faveolata and P. astreoides larvae. Immunohistology using a polyclonal antibody directed against squid rhodopsin indicates the presence of an opsin-like protein localized in epithelial cells of several species of coral larvae, but this antibody did not react with A. palmata.  I am currently developing antibodies against the two, cloned A. palmata opsins in order to localize these pigments in the larvae.  I have also created and am expressing coral-bovine recombinant opsins in mammalian cells (COS-7).  _expression_ will enable me to demonstrate the function and determine the spectral sensitivity of the individual pigments.  

 

 

Benjamin M. Mason

B.S. Biology in 2000, Allegheny College, Meadville, PA

M.S. Marine Biology 2004, UNCW, Wilmington, NC

Entered Ph.D. program in fall 2005

 

 

Advisor:

Dr. Michael Schmale   ____________________________________

 

 

 

 

 

 

 

 

 

Cary Rios
Office of the Dean
University of Miami
Rosenstiel School of Marine & Atmospheric Science
4600 Rickenbacker Cswy
Atrium A VK
P. 305.421.4920
F. 305.421.4711
http://www.rsmas.miami.edu

“If you don't like something, change it. If you can't change it, change your attitude.” Maya Angelou