Ultraviolet Radiation Tolerance in High Elevation Copepods from the Rocky Mountains of Colorado, USA Metadata

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Title

  • Main Title Ultraviolet Radiation Tolerance in High Elevation Copepods from the Rocky Mountains of Colorado, USA

Creator

  • Author: Hudelson, Karista
    Creator Type: Personal

Contributor

  • Chair: Roberts, Aaron P.
    Contributor Type: Personal
    Contributor Info: Major Professor
  • Committee Member: Johnson, Jeff A.
    Contributor Type: Personal
  • Committee Member: Padilla, Pamela
    Contributor Type: Personal
  • Committee Member: Venables, Barney J.
    Contributor Type: Personal

Publisher

  • Name: University of North Texas
    Place of Publication: Denton, Texas
    Additional Info: www.unt.edu

Date

  • Creation: 2011-12

Language

  • English

Description

  • Content Description: Copepods in high elevation lakes and ponds in Colorado are exposed to significant levels of ultraviolet radiation (UV), necessitating development of UV avoidance behavior and photoprotective physiological adaptations. The copepods are brightly pigmented due to accumulation of astaxanthin, a carotenoid which has photoprotective and antioxidant properties. Astaxanthin interacts with a crustacyanin-like protein, shifting its absorbance from 473 nm (hydrophobic free form, appears red) to 632 nm (protein-bound complex, appears blue). In six sites in Colorado, habitat-specific coloration patterns related to carotenoprotein complex have been observed. The objective of this study was to determine whether pigment accumulation or carotenoprotein expression has a greater effect on resistance to UV exposure. For each site, copepod tolerance to UV was assessed by survivorship during UV exposure trials. Average UV exposure was determined for each habitat. Astaxanthin profiles were generated for copepods in each site. Ability to withstand UV exposure during exposure trials was significantly different between color morphs (p < 0.0001). Red copepods were found to tolerate 2-fold greater levels of UVB than blue or mixed copepods. Additionally, red copepods have much higher levels of total astaxanthin than blue or mixed copepods (p < 0.0001) and receive a higher daily UV dose (p < 0.0003). Diaptomid carotenoprotein sequence is not homologous with that of other crustaceans in which crustacyanin has been characterized which prevented quantification of carotenoprotein transcript expression. Overall, diaptomid color morph may be an important indicator of UV conditions in high elevation lentic ecosystems.

Subject

  • Keyword: Copepod
  • Keyword: ultraviolet radiation
  • Keyword: carotenoid
  • Keyword: astaxanthin
  • Keyword: zooplankton
  • Keyword: high elevation lake

Collection

  • Name: UNT Theses and Dissertations
    Code: UNTETD

Institution

  • Name: UNT Libraries
    Code: UNT

Rights

  • Rights Access: public
  • Rights Holder: Hudelson, Karista
  • Rights License: copyright
  • Rights Statement: Copyright is held by the author, unless otherwise noted. All rights Reserved.

Resource Type

  • Thesis or Dissertation

Format

  • Text

Identifier

  • Archival Resource Key: ark:/67531/metadc103331

Degree

  • Academic Department: Department of Biological Sciences
  • Degree Discipline: Environmental Science
  • Degree Level: Master's
  • Degree Name: Master of Science
  • Degree Publication Type: thesi
  • Degree Grantor: University of North Texas

Note