Homeoproteins are defined by the structure of their DNA-binding domain, the homeodomain. Intercellular transfer of homeoprotein was observed ex vivo between animal cells and in vivo in higher plants. In the latter case, transfer is through intercytoplasmic channels that connect plant cells, but these do not exist in animals. Here, we show that the homeodomain of KNOTTED1, a maize homeoprotein, ...

Nuclear transfer experiments in mammals have shown that the nucleus of an adult cell has the ability to direct the development of an entire organism, id est its genome is totipotent. However, these experiments did not conclusively demonstrate that the nuclei of terminally differentiated adult cells remain totipotent. It is possible that rare adult stem cells served as donors for the few survivi...

N uclear transfer is an effective reprogramming strategy that can redirect the utilization of nuclear instructions and ultimately phenotypes (1). When oocytes are used as the host, a somatic cell nucleus can be reprogrammed to activate the earliest stages of embryonic development (2, 3). Nuclear transfer embryos can develop until the stage when they are ready to implant into the uterus or short...