Location: Plant, Soil and Nutrition ResearchTitle: Association of proteomics changes with Al-sensitive root zones in switchgrass
|RANGU, MAHESH - Tennessee State University|
|YE, ZHUJIA - Tennessee State University|
|BHATTI, SARABJIT - Tennessee State University|
|ZHOU, SUPING - Tennessee State University|
|Thannhauser, Theodore - Ted|
Submitted to: Proteomes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/21/2018
Publication Date: 3/22/2018
Citation: Rangu, M., Ye, Z., Bhatti, S., Zhou, S., Fish, T., Yang, Y., Thannhauser, T.W. 2018. Association of proteomics changes with Al-sensitive root zones in switchgrass. Proteomes. 6(2). https://doi.org/10.3390/proteomes6020015.
Interpretive Summary: Aluminum (Al3+) toxicity is a major constraint to plant growth and crop yield in acid soils. However, different plant species differ in their sensitivity to Al. In this study we investigated the impact of Al treatment on protein expression in the root tissue of switchgrass, a major bioenergy crop. A large number of Al-sensitive proteins were identified in apical root tip compared to other morphologically distinct tissues. The molecular functions of the Al-sensitive proteins are consistent with the known cellular activities of the root tissues. We have identified a number of proteins with known roles in Al-tolerance/resistance as well as proteins that have not yet been associated with Al-tolerance mechanisms including several transcription factors. Switchgrass can tolerate Al3+ concentrations at which other crop plants are not viable. This high tolerance to Al3+ suggests that switchgrass is a potential source of new leads for identifying novel Al tolerance genes and mechanisms.
Technical Abstract: In this paper, we report on aluminum (Al)-induced root proteomic changes in switchgrass. After growth in a hydroponic culture system supplemented with 400 uM of Al, plants began to show signs of physiological stress such as a reduction in photosynthetic rate. At this time, the basal 2-cmlong root tips were harvested and divided into two segments, each of 1-cm in length, for protein extraction. Al-induced changes in proteomes were identified using tandem mass tags mass spectrometry (TMT-MS)-based quantitative proteomics analysis. A total of 216 proteins (approximately 3.6% of total proteins) showed significant differences between non-Al treated control and treated groups with significant fold change (twice the standard deviation; FDR adjusted p-value < 0.05). The apical root tip tissues expressed more dramatic proteome changes (164 significantly changed proteins; 3.9% of total proteins quantified) compared to the elongation/maturation zones (52 significantly changed proteins, 1.1% of total proteins quantified). Significantly changed proteins from the apical 1-cm root apex tissues were clustered into 25 biological pathways; proteins involved in the cell cycle (rotamase FKBP 1 isoforms, and CDC48 protein) were all at a reduced abundance level compared to the non-treated control group. In the root elongation/maturation zone tissues, the identified proteins were placed into 18 pathways, among which proteins involved in secondary metabolism (lignin biosynthesis) were identified. Several STRING protein interaction networks were developed for these Al-induced significantly changed proteins. This study has identified a large number of Al-responsive proteins, including transcription factors, which will be used for exploring new Al tolerance genes and mechanisms. Data are available via ProteomeXchange with identifiers PXD008882 and PXD009125.