Comprehensive tissue-specific proteome analysis of drought stress responses in Pennisetum glaucum (L.) R. Br. (Pearl millet)

Abstract

Drought stress is the most limiting factor for plant growth and crop production worldwide. At the same time drought susceptible cereal crops are among the largest producers worldwide. In contrast, Pearl millet is a drought and salt tolerant cereal crop especially used in arid and semi-arid regions by small farmers. The multifactorial molecular mechanisms of this unique drought tolerance are not known. Here, we employ shotgun proteomics for a first characterization of the Pearl millet drought stress proteome. The experimental setup and the data set generated from this study reveal comprehensive physiological and proteomic responses of the drought stressed Pearl millet plants. Our study reveals statistically significant tissue-specific protein signatures during the adaptation to drought conditions. Thus, the work provides a first reference study of the drought stress proteome and related drought responsive proteins (DRP's) in Pearl millet.

Cereal Crop Proteomics: Systemic Analysis of Crop Drought Stress Responses Towards Marker-Assisted Selection Breeding

“…Recently, we performed the first large-scale label-free quantitative shotgun proteomics study of pearl millet leaf, root and seed tissue under drought stress (Ghatak et al, 2016). This allows to compare wheat-specific drought stress protein marker with pearl millet specific drought stress marker.…”

“…Therefore, another aim was also to reveal any differences which correspond to these different types of photosynthesis. For comparison we considered the studies performed by Liu et al (2015), Hajheidari et al (2007), and Ghatak et al (2016) (Supporting Table 1). From these studies, it was evident that rubisco subunits, LEA proteins, ATP synthase, ABA responsive proteins and others can be suggested as an protein marker of drought stress conditions for both wheat and pearl millet.…”

“…The identified ESTs have revealed a major portion of stress responsive genes that may provide a basis to investigate the tolerance of pearl millet to drought stress (Choudhary et al, 2015). In Supporting Table 2 we provide a comparison between these EST markers and our drought stress proteomic markers identified in a recent large-scale proteomics study (Ghatak et al, 2016). A shotgun proteomics approach (GEL-LC-Orbitrap-MS) was employed by us to investigate putative protein markers from different tissues (root, seed, and leaf) under drought stress condition (Ghatak et al, 2016).…”

“…In Supporting Table 2 we provide a comparison between these EST markers and our drought stress proteomic markers identified in a recent large-scale proteomics study (Ghatak et al, 2016). A shotgun proteomics approach (GEL-LC-Orbitrap-MS) was employed by us to investigate putative protein markers from different tissues (root, seed, and leaf) under drought stress condition (Ghatak et al, 2016). In total 2281 proteins were identified and quantified from the harvested root, seed and leaf of which 120 proteins in leaves, 25 proteins in roots and 10 proteins in seeds showed significant changes under drought stress (drought responsive proteins; DRP's).…”

“…Due to the development of robust and reproducible hyphenated techniques such as liquid-chromatography coupled to mass spectrometry label-free-shotgun proteomics has developed into a cornerstone of quantitative proteomics and phosphoproteomics studies which cannot be reviewed here in detail. However, many recent studies from our lab have provided lots of insights in proteome dynamics and adaptation strategies of various plant species and families in stress physiology, development and even field studies of crop plants (Weckwerth et al, 2004; Wienkoop et al, 2004, 2006, 2008; Morgenthal et al, 2005; Hoehenwarter et al, 2008, 2011, 2013; Weckwerth, 2008; Chen et al, 2010; Cerný et al, 2013; Chaturvedi et al, 2013, 2015, 2016; Valledor et al, 2013, 2014; Ischebeck et al, 2014; Paul et al, 2015; Ghatak et al, 2016, in press; Liu et al, 2016; Nukarinen et al, 2016; Wang et al, 2016a,b). Especially, the analysis of posttranslational modifications of proteins is an exclusive approach in proteomics and cannot be covered by any other method.…”