Hybrid (oat×maize) zygotes developed into euhaploid plants with complete oat chromosome complements without maize chromosomes and into aneuhaploid plants with complete oat chromosome complements and different numbers of retained individual maize chromosomes. The elimination of maize chromosomes in the hybrid embryo is caused by uniparental genome loss during early steps of embryogenesis. Some of these haploid plants set seed in up to 50% of their self-pollinated spikelets. The high fertility was found to be mainly caused by formation of numerically unreduced female and male gametes (nunreduced=3x+0…3=21…24 chromosomes). Gamete formation involves meiotic nuclear restitution. The restitution process is caused by an alternative type of meiosis. It follows the model of levigatum-type semi-heterotypic divisions, but with a formation of the nuclear membrane at the transition from telophase I to interkinesis, which resembles the model of pygaera-type pseudo-homotypic divisions. We propose the name haploid meiotic restitution for this particular process combination. We discuss the use and implications of the specific process of gamete formation in F1 (oat×maize) plants.
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http://dx.doi.org/10.1007/s00497-012-0182-7 | DOI Listing |
Sci Rep
January 2025
Animal Genomics Laboratory, Animal Biotechnology Division, ICAR-National Dairy Research Institute, Karnal, Haryana, India.
Poor male fertility significantly affects dairy production, primarily due to low conception rates (CR) in bulls, even when cows are inseminated with morphologically normal sperm. Seminal plasma is a key factor in evaluating the fertilizing ability of bull semen. The extracellular vesicles (EVs) in seminal plasma contain fertility-associated proteins like SPAM1, ADAM7, and SP10, which influence sperm function and fertilizing potential.
View Article and Find Full Text PDFCommun Biol
January 2025
Université Paris Cité, CNRS, Inserm, Institut Cochin, F-75014, Paris, France.
The H3K79 methyltransferase DOT1L is essential for multiple aspects of mammalian development where it has been shown to regulate gene expression. Here, by producing and integrating epigenomic and spike-in RNA-seq data, we decipher the molecular role of DOT1L during mouse spermatogenesis and show that it has opposite effects on gene expression depending on chromatin environment. On one hand, DOT1L represses autosomal genes that are devoid of H3K79me2 at their bodies and located in H3K27me3-rich/H3K27ac-poor environments.
View Article and Find Full Text PDFReprod Fertil Dev
January 2025
CNRS, INRAE, Université de Tours, PRC, Nouzilly, France.
Female infertility, which affects 10-20% of couples worldwide, is a growing health concern in developing countries. It can be caused by multiple factors, including reproductive disorders, hormonal dysfunctions, congenital malformations and infections. In vitro and in vivo studies have shown that plant extracts regulate gonadotropin-releasing hormone, kisspeptin, and gonadotropin expression and/or secretion at the hypothalamic-pituitary level and modulate somatic and germ cells, such as steroidogenesis, proliferation, apoptosis, and oxidative stress at the ovarian level.
View Article and Find Full Text PDFElife
January 2025
Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar, Education City, Qatar Foundation, Doha, Qatar.
The steroid hormone progesterone (P4) regulates multiple aspects of reproductive and metabolic physiology. Classical P4 signaling operates through nuclear receptors that regulate transcription. In addition, P4 signals through membrane P4 receptors (mPRs) in a rapid nongenomic modality.
View Article and Find Full Text PDFMol Reprod Dev
January 2025
Liv Hospital, Centre for Regenerative Medicine and Stem Cell Manufacturing (LivMedCell), İstanbul, Turkey.
In vitro maturation (IVM) is a form of assisted reproductive technology (ART) applied to obtain mature oocytes in culture. Decline in IVM success rates by age has led consideration of novel approaches based on cellular dynamics. Our aim was to achieve proteostasis in old bovine oocytes from 13 to 16-year-old bovine with a lower potential for fertilization.
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