Programmed Cell Death in Developing Brachypodium distachyon Grain
1
Department of Genetics and Genome Biology, University of Leicester, University Road, Leicester LE1 7RH, UK
2
Department of Plant Science and Biotechnology, Abia State University, Uturu PMB 2000, Nigeria
*
Author to whom correspondence should be addressed.
Academic Editors: Petr Smýkal and David Honys
Int. J. Mol. Sci. 2021, 22(16), 9086; https://doi.org/10.3390/ijms22169086
Received: 28 July 2021
/
Revised: 14 August 2021
/
Accepted: 19 August 2021
/
Published: 23 August 2021
(This article belongs to the Special Issue Fruit and Seed Development)
The normal developmental sequence in a grass grain entails the death of several maternal and filial tissues in a genetically regulated process termed programmed cell death (PCD). The progression and molecular aspects of PCD in developing grains have been reported for domesticated species such as barley, rice, maize and wheat. Here, we report a detailed investigation of PCD in the developing grain of the wild model species Brachypodium distachyon. We detected PCD in developing Brachypodium grains using molecular and histological approaches. We also identified in Brachypodium the orthologs of protease genes known to contribute to grain PCD and surveyed their expression. We found that, similar to cereals, PCD in the Brachypodium nucellus occurs in a centrifugal pattern following anthesis. However, compared to cereals, the rate of post-mortem clearance in the Brachypodium nucellus is slower. However, compared to wheat and barley, mesocarp PCD in Brachypodium proceeds more rapidly in lateral cells. Remarkably, Brachypodium mesocarp PCD is not coordinated with endosperm development. Phylogenetic analysis suggests that barley and wheat possess more vacuolar processing enzymes that drive nucellar PCD compared to Brachypodium and rice. Our expression analysis highlighted putative grain-specific PCD proteases in Brachypodium. Combined with existing knowledge on grain PCD, our study suggests that the rate of nucellar PCD moderates grain size and that the pattern of mesocarp PCD influences grain shape.
View Full-Text
Keywords:
Brachypodium distachyon; cereals; grains; programmed cell death; proteases
▼
Show Figures
Figure 1
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
MDPI and ACS Style
Saada, S.; Solomon, C.U.; Drea, S. Programmed Cell Death in Developing Brachypodium distachyon Grain. Int. J. Mol. Sci. 2021, 22, 9086. https://doi.org/10.3390/ijms22169086
AMA Style
Saada S, Solomon CU, Drea S. Programmed Cell Death in Developing Brachypodium distachyon Grain. International Journal of Molecular Sciences. 2021; 22(16):9086. https://doi.org/10.3390/ijms22169086
Chicago/Turabian StyleSaada, Safia, Charles U. Solomon, and Sinéad Drea. 2021. "Programmed Cell Death in Developing Brachypodium distachyon Grain" International Journal of Molecular Sciences 22, no. 16: 9086. https://doi.org/10.3390/ijms22169086
Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.
