Doctor Jwalit Nayak

Candidature

Graduated PhD 2025

Thesis Title

Light-mediated isomerization of carotenoids control nuclear gene expression and regulate metabolic feedback in plants

Research Project

Carotenoids are isoprenoid pigments synthesized in all photosynthetic organisms, as well as some aphids and mites. Lycopene cyclization in the carotenoid pathway diverts into two metabolic branches, one that produces lutein (prevents macular degeneration of the eye) and the other β-carotene (provitamin-A; a precursor to vitamin A that promotes healthy eyesight in animals).

The research will investigate; 1) define the mechanisms by which an apocarotenoid sensing RNA structural switch regulates carotenoid gene expression to fine-tune pathway flux that controls provitamin-A levels, and 2) how different light spectra can control a carotenoid isomerase photo-switch that modulates downstream β-carotene and apocarotenoid derived signals. A significant outcome would be to unravel a new mechanism that can switch on provitamin-A accumulation in horticultural crops.

Publication

Book Chapter

Anwar S, Nayak JJ, Alagoz Y, Wojtalewicz D, Cazzonelli CI, (2022) 'Chapter Two - Purification and use of carotenoid standards to quantify cis-trans geometrical carotenoid isomers in plant tissues', in Carotenoids: Carotenoid and Apocarotenoid Analysis, Edited by Eleanore T. Wurtzel

Journal Articles

Biru FN, Nayak JJ, Waterman JM, Cazzonelli CI, Elbaum R, Johnson SN, (2024) 'Elevated atmospheric CO2 and silicon antagonistically regulate anti-herbivore phytohormone and defence gene expression levels in wheat', Environmental and Experimental Botany, 227, art. no. 105950

Nayak JJ, Anwar S, Krishna P, Chen Z-H, Plett JM, Foo E, Cazzonelli CI, (2022) 'Tangerine tomato roots show increased accumulation of acyclic carotenoids, less abscisic acid, drought sensitivity, and impaired endomycorrhizal colonization', Plant Science, vol.321, Article no.111308

Supervisors

Dr Chris Cazzonelli, Dr Jonathan Plett, Professor Priti Krishna