Ordered Assembly of Mitochondria During Rice Germination Begins with Promitochondrial Structures Rich in Components of the Protein Import Apparatus
Authors: Howell, Katharine; Millar, A.; Whelan, James1
Source: Plant Molecular Biology, Volume 60, Number 2, January 2006 , pp. 201-223(23)
Publisher: Springer
Key:
- Free Content
- New Content
- Subscribed Content
- Free Trial Content
- Free Content
- New Content
- Subscribed Content
- Free Trial Content
Abstract:
Mitochondrial maturation during imbibition of rice embryos follows the transition of unstructured double membrane bound promitochondria to the typical cristae-rich mitochondrial structures observed in mature plant cells. During the first 48 h following imbibition, an ordered increase in the abundance of transcripts encoding mitochondrial proteins was observed. Co-incident with these changes in transcript levels was dynamic and rapid changes in mitochondrial protein content and mitochondrial function. Proteins representing components of the mitochondrial protein import apparatus are strikingly abundant in dry seeds, and a functional import apparatus was shown to operate 2 h after imbibition. Interestingly, this import process was best driven by the oxidation of NADH from outside the mitochondrial inner membrane. In later developmental stages the capacity for matrix organic acid metabolism was evident, accompanied by the appearance of proteins for TCA cycle components, and coordination of electron transport chain assembly through components encoded in both mitochondrial and nuclear genomes. Together these events provide new insights into the understanding of mitochondrial maturation and the nature of promitochondrial structures in plant cells.Keywords: mitochondrial biogenesis; promitochondria; protein import; germination
Document Type: Research article
DOI: 10.1007/s11103-005-3688-7
Key:
- Free Content
- New Content
- Subscribed Content
- Free Trial Content
- Free Content
- New Content
- Subscribed Content
- Free Trial Content
Click here for Page Help