Inter-nucleosomal DNA fragmentation and loss of RNA integrity during seed ageing

Kranner, Ilse, Chen, Hongying, Pritchard, Hugh W, Pearce, Stephen R and Birtić, Simona (2010) Inter-nucleosomal DNA fragmentation and loss of RNA integrity during seed ageing. Journal of Plant Growth Regulation, 63 (1). pp. 63-72. ISSN 0721-7595

Full text not available from this repository.

Abstract

The germination of viable seeds is the basis for new plant growth and development. Seeds lose viability during storage, but the biochemical mechanisms of seed death are not fully understood. This study aimed to investigate degradation patterns of nucleic acids during seed ageing and subsequent water uptake. Seeds of Pisum sativum L. were artificially aged at 50 C and 12 % seed water content (WC). Nucleic acids degradation was studied during ageing and during imbibition of four seed lots with differential viability from highly viable to dead. As seeds lost viability during ageing, DNA was gradually degraded into internucleosomal fragments, resulting in DNA laddering, in conjunction with disintegration of 18S and 28S rRNA bands. During imbibition, non-aged controls had high levels of DNA and RNA integrity through to radicle protrusion. In an aged seed lot with 85 % total germination (TG) DNA fragmentation decreased upon imbibition probably due to nucleosome degradation, while rRNA integrity did not improve. In an aged seed lot with 44 % TG, neither DNA nor rRNA integrity improved upon imbibition. Dead seeds showed DNA degradation as laddering throughout imbibition along with extensive degradation of rRNA. We present a model in which interlinked programmed and non-programmed events contribute to seed ageing, and suggest that protection of nucleic acids during ageing is key to seed longevity.

Item Type: Article
Additional Information: THis work was part of the D.Phil submission for my D.Phil student S. Birtic. Work done in collaboration with Kew (Wakehurst Place).
Depositing User: Stephen Pearce
Date Deposited: 21 Feb 2012 10:01
Last Modified: 22 May 2012 14:46
URI: http://sro.sussex.ac.uk/id/eprint/37663
📧 Request an update