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"HERMAPHRODITIC AXES could have evolved through the simple restriction of B gene expression to part of a conelike structure, yielding both male and female organs on the same axis." https://lnkd.in/dVXk7jP View in LinkedIn

SPECIES INCOMPATIBILITY. "When different yeast species are induced to fuse with each other, their hybrid is unable to proceed smoothly through meiosis, even if all the chromosomes are colinear and syntenic, because a higher level of DNA mismatches provokes the mismatch repair machinery to abort meiotic recombination events, and spores fail to germinate." https://lnkd.in/ebVhXPf View in LinkedIn

TRANSITION ACROSS AXES. "One of the long-standing questions in seed plant evolution was how an ancestor with separate male and female reproductive axes (e.g., pinecones) made the transition to an angiosperm-like plant with hermaphroditic axes (flowers)." https://lnkd.in/dVXk7jP View in LinkedIn

SPECIES BARRIERS. "Modern sexual recognition systems are overwhelmingly prezygotic—cells recognize “self” via pheromones or cell-surface molecules that stimulate zygotic cell fusion—but postzygotic mechanisms have also evolved that permit cells to monitor how similar their chromosomal sequences are with respect to their fusion partner." https://lnkd.in/ebVhXPf View in LinkedIn

FRAGMENT FROM NATURE continues the curated contemplation on flower structure from last weekend. Flowers are an exemplar of many forms in nature, of how they evolved, and why. Being discrete and familiar, these lovely structures can open our minds to the complicated evolutionary paths that led to their current forms, not the least of it is the development of distinct sexes and mixed sex plants. Plants have among the most diverse and interesting types of reproductive strategies. Enjoy the tiptoe through the tulips for this last weekend. View in LinkedIn

SELF MODULES. "Self-recognition modules presumably existed in the protoeukaryotic gene pool that, with evolutionary tinkering, allowed like-like haploid cell adherence to trigger intracellular signals that elicited the conditions for cell–cell fusion." https://lnkd.in/ebVhXPf View in LinkedIn

BLACK BOX. "The stages in the domestication of a proteobacterium into a mitochondrion, a seminal achievement of the protoeukaryote, are not known." http://cshperspectives.cshlp.org/content/6/3/a016154.full View in LinkedIn

HYPOTHESIS. "It is appealing to posit that the combinatorial-control “idea,” originally governing the differentiation of diploid zygotic spores, was co-opted to govern the differentiation of multicellular diploids." http://cshperspectives.cshlp.org/content/6/3/a016154.full View in LinkedIn

"HOMEOPROTEIN (HP) transcription factors are the products of a family of developmental genes with multiple functions, including the definition of body axis, lineage decision and cell/growth cone migration and guidance. They are characterized by their highly conserved 60 amino acid-long DNA-binding domain, the homeodomain (HD)." https://lnkd.in/dchynSE View in LinkedIn

"AN EXPLOSIVE EXPANSION of homeoprotein-encoding genes has accompanied the evolution of multicellularity in animals and land plants, with homeoprotein-based combinatorial control exerted over core domains of the body plan: PBC/MEIS + HOX proteins specify the anterior–posterior axis of animals, and KNOX + BELL proteins specify the initiation of the moss sporophyte program and regulate the architecture of shoot apical meristems." http://cshperspectives.cshlp.org/content/6/3/a016154.full View in LinkedIn