The atypical proteome of mitochondria from mature pollen grainsVisa övriga samt affilieringar
2025 (Engelska)Ingår i: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 35, nr 4, s. 776-787.e5Artikel i tidskrift (Refereegranskat) Published
Abstract [en]
To propagate their genetic material, flowering plants rely on the production of large amounts of pollen grains that are capable of germinating on a compatible stigma. Pollen germination and pollen tube growth are thought to be extremely energy-demanding processes. This raises the question of whether mitochondria from pollen grains are specifically tuned to support this developmental process. To address this question, we isolated mitochondria from both mature pollen and floral buds using the isolation of mitochondria tagged in specific cell-type (IMTACT) strategy and examined their respective proteomes. Strikingly, mitochondria from mature pollen grains have lost many proteins required for genome maintenance, gene expression, and translation. Conversely, a significant accumulation of proteins associated with the tricarboxylic acid (TCA) cycle, the electron transport chain (ETC), and Ca2+ homeostasis was observed. This supports the current model in which pollen requires large quantities of ATP for tube growth but also identifies an unexpected depletion of the gene expression machinery, aligned with the fact that the mitochondrial genome is actively degraded during pollen maturation. Altogether, our results uncover that mitochondria from mature pollen grains are strategically prepared for action by increasing their respiratory capacity and dismantling their gene expression machinery, which raises new questions about the assembly of respiratory complexes in pollen mitochondria, as they rely on the integration of proteins coded by the nuclear and mitochondrial genomes. In addition, the approach described here opens a new range of possibilities for studying mitochondria during pollen development and in pollen-specific mitochondrial events.
Ort, förlag, år, upplaga, sidor
2025. Vol. 35, nr 4, s. 776-787.e5
Nationell ämneskategori
Botanik
Identifikatorer
URN: urn:nbn:se:umu:diva-235849DOI: 10.1016/j.cub.2024.12.037ISI: 001433857300001Scopus ID: 2-s2.0-85217888865OAI: oai:DiVA.org:umu-235849DiVA, id: diva2:1939928
Forskningsfinansiär
Stiftelsen för strategisk forskning (SSF), FFF20- 0008Knut och Alice Wallenbergs StiftelseVinnova2025-02-252025-02-252025-04-24Bibliografiskt granskad