Rxivist logo

Coordinated downregulation of the photosynthetic apparatus as a protective mechanism against UV exposure in the diatom Corethron hystrix

By Robert W. Read, David C. Vuono, Iva Neveux, Carl Staub, Joseph J Grzymski

Posted 24 Jan 2018
bioRxiv DOI: 10.1101/252668 (published DOI: 10.1007/s00253-018-9544-x)

A novel close-coupled and wavelength-configurable platform was designed that allows the precise and repeatable in-vitro irradiation of target organisms to determine their metabolic, protective, mutative, and repair mechanisms as a function of varying levels of specific electromagnetic energy. This new platform and an associated method to quantify near real-time electromagnetic induced stress progression in photoautotrophic organisms, provided a methodology to alter the physiological and metabolic functions of cells in a highly controlled manner. Corethron hystrix was selected as the target for an in-vitro UVR irradiation period of 6-hours followed by a shielded dark period of 6-hours. Irradiation and dark periods were repeated with energy levels beginning at 0.32 mW/cm2 and increasing incrementally to 1.59 mW/cm2. By subjecting the organism to UV induced stress, and observing/recording the physiological and molecular responses at each energy level to both UV induced damage and subsequent repair, we discovered that the cells exhibited a negative linear decrease in the photosynthetic efficiency of photosystem II proportional to UV intensity, corresponding to a large increase in the turnover time of the quinones. Gene expression changes were consistent with UVR induced photosystem II damage with decreased expression of photosystem II reaction center proteins D1, CP43 and CP47. Down-stream metabolic pathways demonstrated mixed expression after UVR irradiation, with strong up-regulation after dark recovery. This ability to alter the physiological, molecular and metabolic makeup of an organism in a highly specific manner is a valuable research and discovery tool in DNA damage research.

Download data

  • Downloaded 214 times
  • Download rankings, all-time:
    • Site-wide: 56,871 out of 78,097
    • In microbiology: 4,197 out of 6,484
  • Year to date:
    • Site-wide: 55,833 out of 78,097
  • Since beginning of last month:
    • Site-wide: 46,727 out of 78,097

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide


Sign up for the Rxivist weekly newsletter! (Click here for more details.)