The DC1-domain protein VACUOLELESS GAMETOPHYTES is essential for female and male gametophyte development in Arabidopsis

CASALONGUÉ, CLAUDIA ANAHÍ; ARIAS, LEONARDO AGUSTÍN; FIOL, DIEGO FERNANDO; D'IPPÓLITO, SEBASTIÁN; PAGNUSSAT, GABRIELA CAROLINA

PLANT JOURNAL

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2017 vol. 90 p. 261 - 275

0960-7412

In this work we identified VACUOLELESS GAMETOPHYTES (VLG) as a DC1 domain containing protein present in the endomembrane system essential for both female and male gametophyte development. VLG was originally annotated as a gene coding for an unknown function protein containing DC1 domains. DC1 domains are cysteine and histidine -rich zinc finger domains found exclusively in the plant Kingdom that have been named based on its similarity with the C1 domain present in protein kinase C (PKC). In Arabidopsis, both male and female gametophytes are characterized by the formation of a big vacuole early in development, which is absent in vlg mutants. As a consequence, development is arrested in embryo sacs and pollen grains at the first mitotic divisions. VLG is specifically located in multivesicular bodies or prevacuolar compartments and our results suggest that vesicular fusion is affected in the mutants, disrupting vacuole formation. Supporting this idea, AtPVA12 - a member of the SNARE vesicle associated protein family and previously related to a sterol binding protein was identified as a VLG interactor. A role for VLG is proposed mediating vesicular fusion in plants as part of the sterol trafficking machinery required for vacuole biogenesis in plants.