tancrei. We observed that synapsis between the two X chromosomes is limited to the short distal (telomeric) regions of the chromosomes in males, leaving the central region completely unsynapsed. This uneven behavior of sex chromosomes during male meiosis is accompanied by structural modifications of...
fulvum, which gave rise to chromosomal rings during F1 meiosis and to low hybrid fertility, suggesting that chromosome translocations accompanied Pisum evolution. To reassess these events in the light of the pea genome assembly, we sequenced single-chromosome samples isolated from three accessions that...
Sex chromosomes experience very different evolutionary forces compared to the rest of the genome, owing to their differential occurrence in males and females. A male-beneficial mutation occurring close to a newly evolved male-determining locus, for instance, is expected to spread, even if highly det...
I Bakloushinskaya,S Matveevsky 摘要: Species of mole voles Ellobius demonstrate a broad variation in sex chromosomes and autosomes, which is unique among mammals. In four species, a Y chromosome was lost, and X0 or XX sex chromosomes in both sexes were obtained. The key testis-determining ...
Or, is the need for sex a function of the unique amitosis of the ciliate macronucleus? The finite life span of animal cells in tissue culture versus the immortality of cultures of cancer cells begs similar questions. That autogamy in ciliates is a stop-gap measure to postpone senescence ...
Australia is home to a unique and unusual fauna of freshwater fishes. Except for two species of Osteoglossidae, almost all Australian freshwater fishes are derived from marine ancestors, a consequence of the continent’s long isolation from other Gondwanan landmasses [1]. This isolation has yiel...
UC1 does not, however, lose the ability to form empty cleistothecia over time in culture, making it a unique strain that is well suited for studying the molecular and morphological stages of cleistothecia formation. At this time, it is unclear whether or not hyphal fusion can occur ...
Endogenous expression of L1 mRNA is the first step in an L1-initiated mutagenesis event. However, the contribution of individual cell types to patterns of organ-specific L1 mRNA expression remains poorly understood, especially at single-locus resolution. We introduce a method to quantify expression ...
Since this event is important to unlock the transduction pathway leading to cell division, this unidentified phosphatase is a critical player of oocyte meiotic division. Here, we identify PP2A-B55δ as the phosphatase that dephosphorylates Arpp19 at S109, thus enabling oocytes to resume meiosis. ...
Sexual reproduction, which involves alternation of meiosis and syngamy, is the ancestral condition of extant eukaryotes. While transitions to asexuality in eukaryotes are frequent, they usually result in a quick extinction1,2. Still, a number of alleged ancient asexual lineages, sometimes referred to...