Dissecting Salt
Stress-Induced Proteomic Changes in Pigeonpea (Cajanus cajan L. Millspaugh) Leaves:
A Detailed Analysis of Stress-Responsive Protein Dynamics
Bangaru Naidu Thaddi
Res. J. Biotech.; Vol. 20(2); 122-133;
doi: https://doi.org/10.25303/202rjbt1220133; (2025)
Abstract
Salinity is a major abiotic stress that poses significant challenges to global agriculture
by reducing crop productivity and soil fertility. In pigeonpea (Cajanus cajan L.
Millspaugh), comprehensive studies investigating proteomic responses to salt stress
are limited. This study aims to establish a detailed proteomic profile for two pigeonpea
varieties: ICPL 87119 (salt-tolerant) and ICPL 85063 (salt-sensitive) under NaCl-induced
salt stress. The study evaluated the effects of different NaCl concentrations (0,
50 mM, 100 mM, 150 mM and 200 mM) on seedling growth including parameters such as
plant height, fresh weight and leaf necrosis. Leaf protein profiles were analyzed
using two-dimensional gel electrophoresis (2-DGE) to identify differentially expressed
proteins under salt stress. Proteins from plants subjected to 150 mM NaCl stress
were identified and characterized using MALDI-TOF-MS with a focus on proteins related
to photosynthesis, ion transport and stress response mechanisms.
Protein spots that exhibited differential expression were analyzed using PDQuest
software. The results showed that salt stress significantly reduced plant growth
and increased leaf necrosis, particularly at higher NaCl concentrations. Key proteins
involved in photosynthesis such as the RuBisCO Large Subunit-Binding Protein Subunit
Beta and ATP Synthase Subunit Beta, were differentially expressed. Proteins associated
with ion transport, including the Glutamine Synthetase Leaf Isozyme and stress response
proteins, such as Heat Shock Protein 7, also showed significant changes in expression.
These findings highlight the critical roles of these proteins in the adaptive response
of pigeonpea to salt stress. This study provides essential insights into the proteomic
dynamics of pigeonpea under salinity, revealing key proteins and pathways involved
in salt tolerance. The identified proteins represent potential targets for future
research and biotechnological interventions to improve crop performance under adverse
conditions.
