bims-plasge 2024-02-04 papers

Issue of 2024–02–04
two papers selected by
Vera S. Bogdanova, ИЦиГ СО РАН

Genetics. 2024 Jan 30. pii: iyae014. [Epub ahead of print]

Maternal mitochondrial function affects paternal mitochondrial inheritance in Drosophila.

Jinguo Cao, Yuying Luo, Yonghe Chen, Zhaoqi Wu, Jiting Zhang, Yi Wu, Wen Hu.

The maternal inheritance of mitochondria is a widely accepted paradigm, and mechanisms that prevent paternal mitochondria transmission to offspring during spermatogenesis and post-fertilization have been described. Although certain species do retain paternal mitochondria, the factors affecting paternal mitochondria inheritance in these cases are unclear. More importantly, the evolutionary benefit of retaining paternal mitochondria and their ultimate fate are unknown. Here we show that transplanted exogenous paternal D. yakuba mitochondria can be transmitted to offspring when maternal mitochondria are dysfunctional in D. melanogaster. Furthermore, we show that the preserved paternal mitochondria are functional, and can be stably inherited, such that the proportion of paternal mitochondria increases gradually in subsequent generations. Our work has important implications that paternal mitochondria inheritance should not be overlooked as a genetic phenomenon in evolution, especially when paternal mitochondria are of significant differences from the maternal mitochondria or the maternal mitochondria are functionally abnormal. Our results improve the understanding of mitochondrial inheritance and provide a new model system for its study.

Keywords: Drosophila ; mt:CoⅠ ; mitochondria transmission; mtDNA; paternal mitochondria inheritance

DOI: https://doi.org/10.1093/genetics/iyae014

Nat Commun. 2024 Feb 02. 15(1): 996

Dysfunction of duplicated pair rice histone acetyltransferases causes segregation distortion and an interspecific reproductive barrier.

Postzygotic reproductive isolation, which results in the irreversible divergence of species, is commonly accompanied by hybrid sterility, necrosis/weakness, or lethality in the F1 or other offspring generations. Here we show that the loss of function of HWS1 and HWS2, a couple of duplicated paralogs, together confer complete interspecific incompatibility between Asian and African rice. Both of these non-Mendelian determinants encode the putative Esa1-associated factor 6 (EAF6) protein, which functions as a characteristic subunit of the histone H4 acetyltransferase complex regulating transcriptional activation via genome-wide histone modification. The proliferating tapetum and inappropriate polar nuclei arrangement cause defective pollen and seeds in F2 hybrid offspring due to the recombinant HWS1/2-mediated misregulation of vitamin (biotin and thiamine) metabolism and lipid synthesis. Evolutionary analysis of HWS1/2 suggests that this gene pair has undergone incomplete lineage sorting (ILS) and multiple gene duplication events during speciation. Our findings have not only uncovered a pair of speciation genes that control hybrid breakdown but also illustrate a passive mechanism that could be scaled up and used in the guidance and optimization of hybrid breeding applications for distant hybridization.

DOI: https://doi.org/10.1038/s41467-024-45377-x