Spatial and temporal nature of reactive oxygen species production and programmed cell death in elm (Ulmus pumila L.) seeds during controlled deterioration

Abstract

Seed deterioration is poorly understood and remains an active area for research. Seeds of elm (Ulmus pumila L.) were aged at 37°C above water [controlled deterioration treatment (CDT)] for various lengths of time to assess programmed cell death (PCD) and reactive oxygen species (ROS) product in embryonic tissues during a 5 d period. The hallmarks of PCD were identified in the elm seeds during CDT including TUNEL experiments, DNA laddering, cytochrome c (cyt c) leakage and enzymatic activities. These analyses indicated that PCD occurred systematically and progressively in deteriorated elm seeds. Cyt c release and increase in caspase-3-like/DEVDase activity occurred during CDT, which could be suppressed by ascorbic acid (AsA) and caspase-3 inhibitor Ac-DEVD-CHO, respectively. In situ localization of ROS production indicated that the distinct spatial-temporal signature of ROS during CDT coincided with the changes in PCD hallmark features. Multiple antioxidant elements were activated during the first few days of CDT, but were subsequently depleted as PCD progressed. Taken together, our findings identify PCD as a key mechanism that occurs asymmetrically during elm seeds CDT and suggest an important role for PCD in seeds deterioration.

Genomics: A Hallmark to Monitor Molecular and Biochemical Processes Leading Toward a Better Perceptive of Seed Aging and ex-situ Conservation

“…In order to develop new tools for monitoring seed aging, qRT-PCR can be used to inspect the expression level of related antioxidative genes (Dona et al, 2013). Recently, Hu et al (2012) reported that controlled deterioration treatment immediately invokes significant increases in caspase-3/DEVDase proteolytic activity. Therefore, qRT-PCR can also be used to detect the expression of the protein in stored seeds.…”

“…DNA alternation has been reported to trigger PCD during seed deterioration Hu et al, 2012). The two basic strategies used to detect DNA alternation efficiently are the identification of DNA laddering, using electrophoreses, and the identification of DNA alteration, using RAPD markers.…”

“…In woody plants like elm (Ulmus pumila L.) seeds, PCD initiates the process of aging (Hu et al, 2012),and when these seeds are subject to c o n t r o l l e d d e t e r i o r a t i o n t r e a t m e n t , t h e electrophoresis of DNA extracted from the seeds exhibits typical DNA laddering, which is recognized as an important characteristic of PCD and apoptotic cell death in plant and animal cells, respectively. Western blot analysis has indicated that mitochondria begin releasing cytochrome C into the cytosol during the second day of controlled deterioration treatment.…”

<b>Lipid peroxidation and antioxidant enzymes of <i>Jatropha curcas</i> L. seeds stored at different maturity stages

“…The seed deterioration process is poorly understood; however, it is an important area of research (Hu et al, 2012). Moreover, J. curcas is progressively gaining importance in several countries due to its high oil content and suitability for biodiesel production (Kumar & Sharma, 2008;Parawira, 2010).…”

“…There are various mechanisms involved in the loss of seed viability during storage; among these mechanisms are lipid peroxidation, enzyme inactivation or protein degradation, cell membrane rupture, and the loss of DNA integrity (McDonald, 1999;Mittler, 2002;Bailly, 2004;Hu et al, 2012;Kumar, Prasad, Banerjee, & Thammineni, 2015). The generation of reactive oxygen species (ROS) and resulting lipid peroxidation, together with the ability of the seeds to remove these radicals, are considered the main causes of seed deterioration (McDonlad, 1999;Bailly, 2004), especially for oilseeds such as J. curcas seeds.…”