Feng Tian

The floral transition in maize represents a pivotal developmental switch that determines flowering time, environmental adaptation, and yield-related traits

Cold stress restricts plant growth and inorganic phosphate (Pi) uptake, reducing yield and increasing fertilizer demand^1,2,3. Enhancing both cold tolerance and phosphorus use efficiency (PUE) is crucial for sustainable crop productivity. Here we identify the SPX-domain-containing E3 ubiquitin ligase NITROGEN LIMITATION ADAPTATION (NLA) as a central regulator that links cold signalling to Pi homeostasis in maize (Zea mays L.). Under cold conditions, NLA promotes the degradation of the transcriptional repressor JAZ11, activating jasmonate signalling to enhance cold tolerance; however, NLA also simultaneously represses Pi uptake, through inositol polyphosphate (InsP)-dependent ubiquitination of the Pi transporter PT4. A ubiquitinome-informed genome-wide association study identified a natural PT4(K267A) (lysine-to-alanine substitution) variant that attenuates NLA-mediated degradation and increases Pi uptake in cold conditions. To overcome this nutrient–stress trade-off, we combined artificial-intelligence-guided structural modelling and ligand docking with genome editing to generate the nla^Δ12 allele, which encodes an NLA variant in which binding to InsP is impaired but JAZ11 targeting is retained. The Δ12 modification selectively redirects the activity of NLA towards jasmonate signalling, resulting in improved cold resilience, higher PUE and increased yield in multi-site field trials. These findings reveal a tunable SPX regulatory module that integrates environmental and nutrient signals, and provide a molecular framework for engineering climate-resilient, nutrient-efficient crops.

3D genome editing reconfigures chromatin loops to fine-tune gene expression for coordinated improvement of multiple crop traits.

Maize (Zea mays L.) is not only an important cereal crop, but also a model plant species for genetic, cytologic, genomic, and molecular studies. Maize possesses tremendous phenotypic and genetic diversity. During the past few decades, researchers have made significant advances in multiple areas, including the genomic compositions and variations of maize and its ancestors, the genetic and genomic bases of maize domestication and evolution, the genetic architecture of various agronomic traits (yield, quality, biotic and abiotic stress responses, nutrient use efficiency, fertility and heterosis), and the development of novel molecular breeding technologies. In this review, we summarize these research achievements and provide a perspective for future maize research and breeding.

A 178-bp copy number variation in the ZmMADS1 promoter represses ZmMADS1 expression and results in delayed flowering, which has been a target of selection during maize spread into higher altitudes. ZmMADS1 promotes maize flowering via the autonomous pathway by directly activating the expression of ZmMADS69 and ZCN8, while repressing ZmRap2.7.