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FRAGMENT FROM NATURE contemplates the question of how animals differ from plants. This may seem like a quaint and perhaps academic question, but it is far from the case. Imagine a creature that continues to form body parts throughout its life, in a quasi pluripotent state, forever capable of regeneration of an adult from a fragment of tissue. This creature can morph its anatomy and physiology according to the conditions. And the delineation of an individual in this creature is essentially a group of cells, not the organism. Read on. View in LinkedIn

TERM CHIMAERAS. "Previous attempts to achieve development to term of aggregation chimaeras between parthenogenetic and fertilised embryos were apparently unsuccessful. We have introduced inner cell masses (ICMs) from diploid, parthenogenetic embryos into intact fertilised mouse blastocysts, and we report here the development of a chimaera to term." https://lnkd.in/gAXZaG6 View in LinkedIn

TRANSITION OF SETS. "The emergence of a new master sex-determining gene on a different chromosome can also lead to a shift of the heterogametic sex, [e.g., transforming a XY system into ZW (nonhomologous transition)]. Such a situation is again represented in the ricefishes. Two species have ZW sex determination on two linkage groups, which are different from those that became the X and the Y in the other five species." http://www.pnas.org/content/112/34/10575.full View in LinkedIn

NEW CHROMOSOMES. "If a gene from elsewhere in the genome becomes the new male sex-determining gene, then a new chromosome will evolve to become the Y (nonhomologous turnover). An increasing number of systems are described where this may have happened." http://www.pnas.org/content/112/34/10575.full View in LinkedIn

CHANGING MASTER GENES. "Even more intriguingly, the master sex-determining gene itself can change; and depending on the type of change, this has different chromosomal consequences. If for example, the function of a gene as a male sex-determining gene is turned over to a different gene, which resides nearby on the same chromosome as the previous master gene, there is no change of the Y chromosome (homologous turnover)." http://www.pnas.org/content/112/34/10575.full View in LinkedIn

JUMPING GENES AND SEX GENES. "Here, recent evidence assigns transposable elements a role in having moved the male sex-determining gene to other chromosomes. As result, the Y chromosome is a different linkage group in several salmonid species. If large pieces or the entire Y are translocated to an autosome, so-called “neo-Y chromosomes” and multiple sex-chromosome systems are created." http://www.pnas.org/content/112/34/10575.full View in LinkedIn

COMMON NEED FOR BODY PLAN. “These special features notwithstanding, plants do develop from a fertilized egg cell, the zygote, during the normal course of their life cycle, and, like animals, have to establish the characteristic body organization of the multicellular adult form.” http://ac.els-cdn.com/0092867495900659/1-s2.0-0092867495900659-main.pdf?_tid=4d4ebb00-9318-11e7-86e1-00000aacb362&acdnat=1504712004_432302d5e397300b77a7d0a78440aca5 View in LinkedIn

UNLIMITED GENERATION. “It is true that the regenerative potential of plants, which is indeed impressive, sets them apart from the more familiar animal models: individual cells can give rise to embryos in culture; localized groups of stem cells called meristems make the adult plant in a seemingly autonomous fashion not only during normal development, but also from regeneration from lumps of undifferentiated cells in culture.” https://lnkd.in/gHns7zY View in LinkedIn

“POSTEMBRYONIC DEVELOPMENT of the animal consists of the enlargement of the body” not of growing new body parts unlike plants. https://lnkd.in/gwMHxei View in LinkedIn

INTERFACE. “Plant cells are highly resistant to oncogenic transformation. This review discusses the role that cell-cycle regulators may have at the interface between cell division and differentiation, and in the context of the high plasticity of plant cells.” https://lnkd.in/g8-4Y_M View in LinkedIn