Large-scale Identification and Time-course Quantification of Ubiquitylomes in De-etiolating Maize Seedling Leaf

ABSTRACT: Ubiquitylation is a widely known post-translational modification that regulates myriad biochemical and physiological events in organism. The ubiquitin system is crucial for the development and fitness of higher plants. The process of de-etiolation, during which green plants initiate photomorphogenesis and establish autotrophy, is a dramatic and complicated procedure under the tight regulation of massive ubiquitylation/de-ubiquitylation events. Here we present site-specifically quantified proteomic data of the ubiquitylomes in seedlings’ first leaves of a globally important crop and C4 model plant, Zea Mays, in etiolated state and early de-etiolating states (exposed to light for one, six and twelve hours, respectively), achieved through an immunoprecipitation-based high-resolution mass spectroscopic (MS) method. In our composite data of multiple ubiquitylomes, 1926 unique ubiquitylation sites corresponding to 1041 proteins were identified and quantified, based on which five potential ubiquitylation motifs, KA, AXK, KXG,AK and TK were found. The time-course fold change of the ubiquitylation levels of 214 sites corresponding to 172 proteins were detected to be highly correlated in two technical replicates of MS experiments; evident fold changes (>1.5 fold) of the ubiquitylation levels of 78 sites during the 12 hours’ de-etiolation process were detected. A majority of the ubiquitylated sites we identified corresponded to substrates involving protein and DNA metabolism, such as ribosome and histone; meanwhile, multiple ubiquitylation sites in proteins reflecting plant’s major physiological changes during de-etiolation, including hormone synthesis/signaling, key C4 photosynthetic enymes, light signaling proteins were identified. This proteomic study on the ubiquitylome of de-etiolating maize seedling leaf is the first attempt ever of studying the ubiquitylome of C4 plant.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Zea Mays (maize)

TISSUE(S): Leaf

SUBMITTER: Tiancong Lu  

LAB HEAD: Baichen Wang

PROVIDER: PXD007880 | Pride | 2020-04-09

REPOSITORIES: Pride