Project description:Transcriptional profiling of 4 maize varieties comparing genetic root response under control temperature conditions with genetic root response under low temperature conditions
Project description:Development of crop varieties with high nitrogen use efficiency (NUE) is crucial for minimizing N loss, reducing environmental pollution and decreasing input cost. Maize is one of the most important crops cultivated worldwide and its productivity is closely linked to the amount of fertilizer used. A survey of the transcriptomes of shoot and root tissues of a maize hybrid line and its two parental inbred lines grown under sufficient and limiting N conditions by mRNA-Seq has been conducted to have a better understanding of how different maize genotypes respond to N limitation.
Project description:These maize (Zea mays L.) B73 cellular RNA samples were prepared from seedlings treated in 2 h water and extracted cellular RNA directly from frozen 1-mm root tips. They are parallel experiment to compare to two other types of RNA extracted from isolated nuclei.
Project description:Investigation of whole genome gene expression level changes in maize plants (standard maize line B73) in controlled conditions under continuous light. Tissues of the leaf elongation zone were sampled from plants well watered every 12 hours before and after lights on.
Project description:Nitrogen (N) is an essential macronutrient for agricultural production, and its excessive use causes not only economic but also environmental damage. However, improving nitrogen use efficiency (NUE) remains a complex task for achieving more productive crops under conditions of limited nitrogen availability. To the best of our knowledge, this is the first study aiming to integrate the morphophysiological responses and proteomic profiles of leaves and roots of popcorn (Zea mays everta). For this, two inbred lines contrasting for NUE, i.e., P2 (high NUE) and L80 (low NUE), were cultivated under high (100% of N supply) and low (10% of N supply) nitrogen conditions. Morphological and physiological traiits such as photochemical quenching (qP), non-photochemical quenching (NPQ), quantum yield of photosystem II (ΦPSII), and potential photosynthesis (Apot) were evaluated. P2 showed more pronounced vegetative growth under low N, as well as higher values of qP, NPQ, and ΦPSII. Comparative proteomic analysis of the leaves identified 215 differentially accumulated proteins (DAPs) in P2 and 168 DAPs in L80, while in roots, 127 DAPs were observed in P2 and 172 in L80. In leaves, DAPs involved in the response to oxidative stress, energy metabolism, and photosynthesis represented the main differences between P2 and L80. In roots, DAPs involved in nitrate transport, ammonium assimilation, and amino acid metabolism seem to have contributed to the improved NUE in P2. This study provides valuable insights into the molecular mechanisms underlying NUE and opens avenues for molecular breeding aimed at selecting superior genotypes for the development of a more sustainable agriculture.
Project description:Nitrate (NO3-) is crucial for optimal plant growth and development and often limits crop productivity at the low availability. In comparison with model plant Arabidopsis, the molecular mechanisms underlying NO3- acquisition and utilization remain largely unclear in maize. In particular, only a few genes have been exploited to improve nitrogen use efficiency (NUE). Here, we demonstrated that NO3--inducible ZmNRT1.1B (ZmNPF6.6) positively regulated NO3--dependent growth and NUE in maize. We showed that the tandem duplicated proteoform ZmNRT1.1C is irrelevant to maize seedling growth under nitrate supply, however, loss-of-function of ZmNRT1.1B significantly weakened plant growth under adequate NO3- supply in both hydroponic and field conditions. 15N-labeled NO3- absorption assay indicated that ZmNRT1.1B mediated high-affinity NO3--transport and root-to-shoot NO3- translocation. Furthermore, upon NO3- supply, ZmNRT1.1B promotes cytoplasmic-to-nuclear shuttling of ZmNLP3.1 (ZmNLP8), which co-regulates the expression of genes involved in NO3- response, cytokinin biosynthesis and carbon metabolism. Remarkably, overexpression of ZmNRT1.1B in modern maize hybrids improved grain yield under nitrogen (N) limiting fields. Taken together, our study revealed a crucial role of ZmNRT1.1B in high-affinity NO3- transport and signaling and offers valuable genetic resource for breeding nitrogen use efficient high-yield cultivars.
Project description:In this study a transcriptomic approach (RNA-sequencing) was utilized to elucidate molecular responses of maize (Zea mays L.) primary roots of the inbred line B73 to water deficit to gain a better understanding of the mechanisms underlying drought tolerance. Kernels of the maize inbred line B73 were germinated in paper rolls soaked with distilled water until seedlings had a primary root length of 2 to 4 cm. For mild and severe water deficit conditions, seedlings were transferred to PEG8000 solution with water potentials of -0.2 MPa and -0.8 MPa, respectively. Water deficit treatment was applied for 6 h and 24 h. Each treatment was performed in four biological replicates each consisting of 10 roots.