Genome survey sequencing of wild cotton (Gossypium robinsonii) reveals insights into proteomic responses of pollen to extreme heat

Pinpointing the timing of meiosis: a critical factor in evaluating the impact of abiotic stresses on the fertility of cereal crops

The development of male gametes, vital to sexual reproduction in crops, requires meiosis followed by successive mitotic cell divisions of haploid cells. The formation of viable pollen is especially vulnerable to abiotic stress, with consequences both for yield and for grain quality. An understanding of key molecular responses when specific stages during pollen development are subjected to stress (e.g. heat) is possible only when sampling is carefully informed by developmental biology. Traditionally, morphological characteristics have been commonly used in cereals as 'indicators' of male reproductive stages. We argue that these morphological attributes are strongly influenced by genotype and genotype-environment interactions and cannot be used reliably to define developmental events during microsporogenesis and microgametogenesis. Furthermore, asynchronous development along the axis of a single inflorescence calls for selective sampling of individual florets to define specific reproductive stages accurately. We therefore propose guidelines to standardise the sampling of cells during male reproductive development, particularly when interrogating the impact of stress on susceptible meiosis. Improved knowledge of development will largely negate the variability imposed by genotype, environment and asynchronous development of florets. Highlighting the subtleties required for sampling and investigation of male reproductive stages will make the selection of abiotic stress-tolerant cereal genotypes more reliable.

Unraveling the genetic and molecular basis of heat stress in cotton

Human activities and climate change have resulted in frequent and intense weather fluctuations, leading to diverse abiotic stresses on crops which hampers greatly their metabolic activities. Heat stress, a prevalent abiotic factor, significantly influences cotton plant biological activities resulting in reducing yield and production. We must deepen our understanding of how plants respond to heat stress across various dimensions, encompassing genes, RNAs, proteins, metabolites for effective cotton breeding. Multi-omics methods, primarily genomics, transcriptomics, proteomics, metabolomics, and phenomics, proves instrumental in studying cotton's responses to abiotic stresses. Integrating genomics, transcriptomics, proteomics, and metabolomic is imperative for our better understanding regarding genetics and molecular basis of heat tolerance in cotton. The current review explores fundamental omics techniques, covering genomics, transcriptomics, proteomics, and metabolomics, to highlight the progress made in cotton omics research.

A universal protocol for high-quality DNA and RNA isolation from diverse plant species

Next-generation sequencing demands high-quality nucleic acid, yet isolating DNA and RNA is often challenging, particularly from plant tissues. Despite advances in developing various kits and reagents, these products are tailored to isolation of nucleic acid from model plant tissues. Here we introduce a universal lysis buffer to separate nucleic acid from various plant species, including recalcitrant plants, to facilitate molecular analyses, such as quantitative PCR (qPCR), transcriptomics, and whole-genome sequencing (WGS). The protocol is a modification of the original CTAB methods, which leads to nucleic acid isolation from many plant species, including monocots and eudicots. The lysis buffer consists of hexadecyltrimethylammonium bromide (CTAB), sodium chloride (NaCl), Tris base, ethylenediaminetetraacetic acid (EDTA) and β-mercaptoethanol (βME). The modified CTAB method enables the isolation of nucleic acid from small amounts of plant tissues (e.g., 15-100 mg) in a timely manner, which is well-suited for a large number of samples and also when adequate sample collection is a limiting factor. The protocol isolates not only DNA from various plant species but also RNA. This makes it highly effective for molecular analyses compared to previously described CTAB methods optimised for DNA isolation. The appropriate concentration of the components enables high-quality DNA and RNA isolation from plant tissues simultaneously. Additionally, this protocol is compatible with commercially available columns. For DNA and RNA to be qualified for next-generation sequencing platforms, the protocol is supplemented with columns to purify either DNA or RNA from the same tissue to meet high standards for sequencing analyses. This protocol provides an ideal approach to overcome potential obstacles in isolating high-quality DNA or RNA from a wide range of plant species for downstream molecular analysis.