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Meyberg, R.

Publications and source records attributed to Meyberg, R..

2 recordsLinked to original sources

DELLA proteins regulate spore germination and reproductive development in Physcomitrium patens.

O_LIProteins of the DELLA family integrate environmental signals to regulate growth and development throughout the plant kingdom. Plants expressing non-degradable DELLA proteins underpinned the development of high-yielding Green Revolution dwarf crop varieties in the 1960s. In vascular plants, DELLAs are regulated by gibberellins, diterpenoid plant hormones. How DELLA protein function has changed during land plant evolution is not fully understood. C_LIO_LIWe have examined the function and interactions of DELLA proteins in the moss Physcomitrium (Physcomitrella) patens, in the sister group of vascular plants (Bryophytes). C_LIO_LIPpDELLAs do not undergo the same regulation as flowering plant DELLAs. PpDELLAs are not degraded by diterpenes, do not interact with GID1 gibberellin receptor proteins and do not participate in responses to abiotic stress. PpDELLAs do share a function with vascular plant DELLAs during reproductive development. PpDELLAs also regulate spore germination. PpDELLAs interact with moss-specific photoreceptors although a function for PpDELLAs in light responses was not detected. PpDELLAs likely act as hubs for transcriptional regulation similarly to their homologues across the plant kingdom. C_LIO_LITaken together, these data demonstrate that PpDELLA proteins share some biological functions with DELLAs in flowering plants, but other DELLA functions and regulation evolved independently in both plant lineages. C_LI

plant biology↗

Characterization of evolutionarily conserved key players affecting eukaryotic flagellar motility and fertility using a moss model

Defects in flagella/cilia are often associated with infertility and disease. Motile male gametes (sperm cells) with flagella are an ancestral eukaryotic trait that has been lost in several lineages, for example in flowering plants. Here, we made use of a phenotypic male fertility difference between two moss (Physcomitrella patens) strains to explore spermatozoid function. We compare genetic and epigenetic variation as well as expression profiles between the Gransden and Reute strain to identify a set of genes associated with moss male infertility. Defects in mammal and algal homologs of these genes coincide with a loss of fertility, demonstrating the evolutionary conservation of flagellar function related to male fertility across kingdoms. As a proof of principle, we generated a loss-of-function mutant of a coiled-coil domain containing 39 (ccdc39) gene that is part of the flagellar hydin network. Indeed, the Ppccdc39 mutant resembles the male infertile Gransden strain phenotype. Potentially, several somatic (epi-)mutations occurred during prolonged vegetative propagation of P. patens Gransden, causing regulatory differences of e.g. the homeodomain transcription factor BELL1. Probably these somatic changes are causative for the observed male fertility. We propose that P. patens spermatozoids might be employed as an easily accessible system to study male infertility of human and animals.

plant biology↗