Biology subjects

Chen, Y.-Z.

Publications and source records attributed to Chen, Y.-Z..

2 recordsLinked to original sources

bioRxiv2024

MOS4-Associated Complex subunits 3A and 3B modulate FLM splicing to repress photoperiod-dependent floral transition

Plants adjust their flowering time by integrating environmental cues through complex regulatory networks. RNA splicing plays a crucial role in modulating gene expression in response to flowering signals. The MOS4-associated complex (MAC), consisting of the evolutionarily conserved E3 ubiquitin ligases MAC3A and MAC3B, is pivotal in splicing regulation. However, their involvement in floral transition remained unclear. This study observed that mac3a/mac3b mutants flowered significantly earlier under short-day (SD) conditions, a phenotype absent under long-day (LD) conditions. This early flowering correlated with upregulation of FLOWERING LOCUS T (FT) and SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1) compared to wild-type plants. Transcriptomic analysis revealed alterations in transcript levels and splicing profiles of key floral regulators across different flowering pathways. Further investigation identified the thermosensory flowering regulator FLOWERING LOCUS M (FLM) as being influenced by MAC3A and MAC3B. Subsequently, we found that MAC3A and MAC3B exhibited higher expression and were associated with FLM transcripts to modulate their splicing in SD. This study elucidates how the MAC complex, through RNA splicing regulation, integrates environmental signals to modulate flowering, unveiling a new layer of complexity in flowering pathways crosstalk under non-inductive photoperiods.

plant biology↗

bioRxiv2023

Mitotic events depend on regulation of PLK-1 levels by the mitochondrial protein SPD-3

In metazoans, Polo Kinase (Plk1) controls several mitotic events including nuclear envelope breakdown, centrosome maturation and kinetochore assembly. Here we show that mitotic events regulated by Polo Like Kinase (PLK-1) in early C. elegans embryos depend on the mitochondrial-localized protein SPD-3. spd-3 mutant one-cell embryos contain abnormally positioned mitotic chromosomes and prematurely and asymmetrically disassemble the nuclear lamina. Nuclear envelope breakdown (NEBD) in C. elegans requires direct dephosphorylation of lamin by PLK-1. In spd-3 mutants PLK-1 levels are ~6X higher in comparison to control embryos and PLK-1::GFP was highly accumulated at centrosomes, the nuclear envelope, nucleoplasm, and chromosomes prior to NEBD. Partial depletion of plk-1 in spd-3 mutant embryos rescued mitotic chromosome and spindle positioning defects indicating that these phenotypes result from higher PLK-1 levels and thus activity. Our data suggests that the mitochondrial SPD-3 protein controls NEBD and chromosome positioning by regulating the endogenous levels of PLK-1 during early embryogenesis in C. elegans. This finding suggests a novel link between mitochondria and mitotic events by controlling the amount of a key mitotic regulator, PLK-1 and thus may have further implications in the context of cancers or age-related diseases and infertility as it provides a novel link between mitochondria and mitosis.

cell biology↗