Human cloning refers to the production of genetically identical humans. This cloning is possible via either ‘‘embryo splitting’’ or ‘‘nuclear transfer’’. Embryo splitting involves the separation of an early human embryo into two or more parts. Each of these parts has the potential to develop into a blastocyst (late embryo), which, if implanted, can develop into a child. This is how genetically ...

Asymmetric localisation of mRNA transcripts to specific sites within the cytoplasm is a widely employed mechanism for targeting of proteins and generating cell polarity. The mechanism and function of mRNA localisation has been extensively studied in Drosophila melanogaster, where, for example, the Egalitarian/BicaudalD/dynein complex mediates transport of mRNA transcripts, towards microtubule m...

Oocyte maturation is associated with suppression of transcriptional activity. Consequently, gene expression during oocyte maturation, fertilization and early embryo development, until zygotic genome activation (ZGA) is primarily regulated by translational activation of maternally derived mRNAs. Embryonic poly(A)-binding protein (EPAB) is the predominant poly(A)-binding protein in Xenopus, mouse...

In vertebrates, growth hormone/insulin-like growth factor (GH/IGF) axis signaling plays a critical role in regulating somatic growth. Understanding the direct upstream regulators of GH/IGF axis remains a major challenge. Our studies of the zebrafish reveal that the conserved miR-200 family members are critical regulators of embryo size by targeting several GH/IGF axis genes, including GH, GHRa,...

The cytoskeleton of the mammalian egg and early embryo is highly unique when compared to the cytoskeleton of their somatic cell brethren. Although all three cytoskeletal systems, actin filaments, microtubules, and intermediate filaments, are present as early as the unfertilized egg; each system has adapted features that allow the egg and early embryo to meet the strict demands of the developmen...

The study was undertaken to examine the effect of two synthetic auxins on somatic embryogenesis and plant regeneration from mature embryo explants of 16 onion cultivars. Cotyledons were removed from the embryos and remaining portions were cultured on MS medium supplemented with 1.0 mg/L 2,4-D and 5.0 mg/L picloram alone or in combination (1.0 mg/L 2,4-D + 2.5 mg/L picloram) to produce embryogen...

The ability to obtain genetically identical offspring in cattle (clones) is useful for research and for potential applications to breeding schemes. Experimental possibilities for generating such animals have evolved considerably in the last two decades. Embryo splitting has become a relatively simple technique but is limited to twinning. Embryonic nuclear transfer has improved and is associated...

A reliable regeneration system for faba bean has been difficult to establish and therefore, the genetic improvement of Vicia faba L. was delayed. The paper describes a method of somatic embryo induction in callus of V. faba. Two Egyptian faba bean cultivars 'Giza 2' and '24 Hyto' were used. Callus was induced from epicotyls and shoot tips cultured on MS or Gamborg medium supplemented with 3% su...

This work describes an improved and efficient method for optimum maturation and normal embryo growth to produce healthy plantlets through somatic embryogenesis using suspension cultures for date palm cv. sakkoty. cell suspensions were supplemented with low amounts of dichlorophenoxyacetic acid (0.5mg/1) and different concentrations of abscise acid (AbA) (0.1, 0.3 and 0.5 mg/l) and polyethylene ...

The East Indian sandalwood tree, Santalum album, yields one of the costliest heartwoods and precious essential oil. Unsurprisingly, this endangered forest species is severely affected due to unmet global demands, illegal trade and harvesting, overharvesting and an epidemic mycoplasmal spike disease. In vitro micropropagation endeavours have resulted in defined in vitro stages such as somatic em...