Sex in Symbiodiniaceae dinoflagellates: genomic evidence for independent loss of the canonical synaptonemal complex

Dinoflagellates of the Symbiodiniaceae family encompass diverse symbionts that are critical to corals and other species living in coral reefs. It is well known that sexual reproduction enhances adaptive evolution in changing environments. Although genes related to meiotic functions were reported in...

Full description

Saved in:
Bibliographic Details
Published in:Scientific reports 2020-06, Vol.10 (1), p.9792-9792, Article 9792
Main Authors: Shah, Sarah, Chen, Yibi, Bhattacharya, Debashish, Chan, Cheong Xin
Format: Article
Language:English
Subjects:
631/1647/2217/748
631/181/2474
631/208/212
631/326/325
Biological Evolution
Chromosomes
Ciliates
Codon Usage
Coral reefs
Corals
Datasets as Topic
Dinoflagellata
Dinoflagellates
Dinoflagellida - genetics
Dinoflagellida - physiology
Environmental changes
Evolution & development
Evolutionary genetics
Fertilization
Gene expression
Gene Expression Profiling
Genome, Protozoan
Genomes
Humanities and Social Sciences
Meiosis
Meiosis - genetics
Microorganisms
multidisciplinary
Protein structure
Science
Science (multidisciplinary)
Selection, Genetic
Sex
Sexual reproduction
Symbiodiniaceae
Symbionts
Synaptonemal complex
Synaptonemal Complex - genetics
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Dinoflagellates of the Symbiodiniaceae family encompass diverse symbionts that are critical to corals and other species living in coral reefs. It is well known that sexual reproduction enhances adaptive evolution in changing environments. Although genes related to meiotic functions were reported in Symbiodiniaceae, cytological evidence of meiosis and fertilisation are however yet to be observed in these taxa. Using transcriptome and genome data from 21 Symbiodiniaceae isolates, we studied genes that encode proteins associated with distinct stages of meiosis and syngamy. We report the absence of genes that encode main components of the synaptonemal complex (SC), a protein structure that mediates homologous chromosomal pairing and class I crossovers. This result suggests an independent loss of canonical SCs in the alveolates, that also includes the SC-lacking ciliates. We hypothesise that this loss was due in part to permanently condensed chromosomes and repeat-rich sequences in Symbiodiniaceae (and other dinoflagellates) which favoured the SC-independent class II crossover pathway. Our results reveal novel insights into evolution of the meiotic molecular machinery in the ecologically important Symbiodiniaceae and in other eukaryotes.
ISSN:2045-2322
2045-2322
DOI:10.1038/s41598-020-66429-4