Surely we can see that the autosonal regions are also responsible for the addadicktome triggers.
If an active Y which contains maleness is the mechanism by which the male parts of a plant are made, then again I ask where that info comes from in a female treated with chems to force the maleness to express itself.
If an active Y which contains maleness is the mechanism by which the male parts of a plant are made, then again I ask where that info comes from in a female treated with chems to force the maleness to express itself.
is it that bad?,,,, thanks for thinking about it ither way Green
im finding it had to get a copy of that paper your referencing for free ,,,,,ive only read the abstract,,but couldnt the recombination of [PAR] be part of a more complex transpoon type activity?,,,,,,as far as i can tell there is only indirect evidence of an Active Y,,not direct evidence,,,,,please correct me if im wrong..
but i am quoting from papers after [2005] now,,,,,,,,,,,
[E Kejnovsky, R Hobza, T Cermak, Z Kubat and B Vyskot. 2009]
The trajectory from autosomes to sex chromosomes may start with the emergence of a sex-determining gene with one allele that determines male individuals and the other female individuals. A two-loci model was suggested by Charlesworth et al. (2005) in which mutation in one gene on the proto-X chromosome results in male sterility and mutation in another gene on the proto-Y chromosome results in female sterility. Acquisition of a sex-determining gene(s) may be followed by the suppression of recombination in the vicinity of the gene(s). Later, other sex-determining genes that influence the development of a particular sex, or are antagonistic to the opposing sex, may accumulate around the sexdetermining gene. Such sex-determining regions can, in some instances, translocate between chromosomes and create new sex chromosomes (Traut and Willhoeft, 1990; Willhoeft and Traut, 1990; Traut and Wollert, 1998). The initiating mechanisms of recombination suppression are not yet clear, though some models based on epigenetic silencing (Jablonka, 2004) or inversions (Lahn and Page,1999) have been proposed. Zluvova et al. (2005) suggested that the inversion on the Y chromosome of Silene latifolia is a consequence of recombination arrest as opposed to its cause. In addition, non-recombining regions may expand through the accumulation of repetitive DNA sequences (Charlesworth, 1991), which often form heterochromatin. Ultimately the processes, because of a lack of recombination in meiosis, may lead to a lower expression of the Y-linked genes and eventually to their degeneration into pseudogenes (Bachtrog, 2006; Marais et al., 2008). Once the Y chromosome has become a genetic desert, the balance between mechanisms that expand the chromosome (for example, transposition) and those that cause it to contract (for example, deletions), will govern the longterm fate of the chromosome. At this stage, large regions of the Y chromosome without genes are dispensable and can be lost. It is not clear yet whether the processes of gene degeneration, TEs accumulation and expansions on one hand and contractions on the other hand are stepwise or are occurring simultaneously. However, the lifetime of an old Y chromosome is often prolonged by the addition of segments transferred from autosomes (Graves, 2005). Acquisition of new genes from autosomes mediated by retrotransposition has been shown in humans (Lahn and Page, 1999), and a similar duplicative transfer has also been shown in the young Y chromosomes of Silene latifolia (Matsunaga et al., 2003). A final possibility is that sex is determined not by the specific Y-linked gene, but only by the ratio of X chromosome to autosomes (X/A ratio). Then the Y chromosome either remains as a genetic entity or could be lost entirely. A new autosomal pair can then be chosen to become a new pair of sex chromosomes and the cyclic process can continue. The persistence of the Y chromosome indicates that it can repeatedly arise de novo, for example, by the fusion between an autosome and an X chromosome followed by the fixation of the neo-X and the neo-Y chromosomes as was shown in grasshopper Podisma pedestris (Westerman and Hewitt, 1985; Veltsos et al., 2008)
http://www.evolucnigenomika.cz/pdf/Kejnovsky_09_Heredity.pdf
The active male linked Y that is responsible for the production of a plant's maleness may just be coding for a certain type or types of hormones/proteins that activate the part of the genome that contains the physical architecture of maleness. The sex reversal treatments likely mimic this natural system.
In other words: the sex determinism genes aren't the sex differentiation genes.