A phytochrome/phototropin chimeric photoreceptor promotes growth of fern gametophytes under limited light conditions.
J Exp Bot
; 75(8): 2403-2416, 2024 Apr 15.
Article
em En
| MEDLINE
| ID: mdl-38189579
ABSTRACT
Many ferns thrive even in low-light niches such as under an angiosperm forest canopy. However, the shade adaptation strategy of ferns is not well understood. Phytochrome 3/neochrome (phy3/neo) is an unconventional photoreceptor, found in the fern Adiantum capillus-veneris, that controls both red and blue light-dependent phototropism and chloroplast photorelocation, which are considered to improve photosynthetic efficiency in ferns. Here we show that phy3/neo localizes not only at the plasma membrane but also in the nucleus. Since both phototropism and chloroplast photorelocation are mediated by membrane-associated phototropin photoreceptors, we speculated that nucleus-localized phy3/neo possesses a previously undescribed biological function. We reveal that phy3/neo directly interacts with Adiantum cryptochrome 3 (cry3) in the nucleus. Plant cryptochromes are blue light receptors that transcriptionally regulate photomorphogenesis; therefore, phy3/neo may function via cry3 to synchronize light-mediated development with phototropism and chloroplast photorelocation to promote fern growth under low-light conditions. Furthermore, we demonstrate that phy3/neo regulates the expression of the Cyclin-like gene AcCyc1 and promotes prothallium expansion growth. These findings provide insight into the shade adaptation strategy of ferns and suggest that phy3/neo plays a substantial role in the survival and growth of ferns during the tiny gametophytic stage under low-light conditions, such as those on the forest floor.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fitocromo
/
Gleiquênias
Idioma:
En
Revista:
J Exp Bot
Assunto da revista:
BOTANICA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Japão