RT Journal Article SR Electronic T1 Altering nuclear import in early Xenopus laevis embryos affects later development JF bioRxiv FD Cold Spring Harbor Laboratory SP 510313 DO 10.1101/510313 A1 Predrag Jevtić A1 Daniel L. Levy YR 2019 UL http://biorxiv.org/content/early/2019/01/02/510313.abstract AB More than just a container for DNA, the nucleus carries out a wide variety of critical and highly regulated cellular functions. One of these functions is nuclear import, and in this study we investigate how altering nuclear import impacts developmental progression and organismal size. During early Xenopus laevis embryogenesis, the timing of a key developmental event, the midblastula transition (MBT), is sensitive to nuclear import factor levels. How might altering nuclear import and MBT timing in the early embryo affect downstream development of the organism? We microinjected X.laevis two-cell embryos to increase levels of importin α or NTF2, resulting in differential amounts of nuclear import factors in the two halves of the embryo. Compared to controls, these embryos exhibited delayed gastrulation, curved neural plates, and bent tadpoles with different sized eyes. Furthermore, embryos microinjected with NTF2 developed into smaller froglets compared to control microinjected embryos. We propose that altering nuclear import and size affects MBT timing, cell size, and cell number, subsequently disrupting later development. Thus, altering nuclear import early in development can affect function and size at the organismal level.AbbreviationsNEnuclear envelopeMBTmidblastula transitionhpfhours post fertilizationdpfdays post fertilizationNTF2nuclear transport factor 2LB3lamin B3imp αimportin αNLSnuclear localization signalNPCnuclear pore complex