Structure of a heterogeneous, glycosylated, lipid-bound, in vivo-grown protein crystal at atomic resolution from the viviparous cockroach Diploptera punctata.

Macromolecular crystals for X-ray diffraction studies are typically grown in vitro from pure and homogeneous samples; however, there are examples of protein crystals that have been identified in vivo. Recent developments in micro-crystallography techniques and the advent of X-ray free-electron lasers have allowed the determination of several protein structures from crystals grown in cellulo. Here, an atomic resolution (1.

Methoprene-tolerant (Met) knockdown in the adult female cockroach, Diploptera punctata completely inhibits ovarian development.

Independent of the design of the life cycle of any insect, their growth and reproduction are highly choreographed through the action of two versatile hormones: ecdysteroids and juvenile hormones (JH). However, the means by which JH can target tissues and exert its pleiotropic physiological effects is currently still not completely elucidated. Although the identity of the one JH receptor is currently still elusive, recent evidence seems to point to the product of the Methoprene-tolerant gene (Met) as the most likely contender in transducing the action of JH.

In vivo crystallography at X-ray free-electron lasers: the next generation of structural biology?

The serendipitous discovery of the spontaneous growth of protein crystals inside cells has opened the field of crystallography to chemically unmodified samples directly available from their natural environment. On the one hand, through in vivo crystallography, protocols for protein crystal preparation can be highly simplified, although the technique suffers from difficulties in sampling, particularly in the extraction of the crystals from the cells partly due to their small sizes. On the other hand, the extremely intense X-ray pulses emerging from X-ray free-electron laser (XFEL) sources, along with the appearance of serial femtosecond crystallography (SFX) is a milestone for radiation damage-free protein structural studies but requires micrometre-size crystals.

Diploptera punctata as a model for studying the endocrinology of arthropod reproduction and development.

The Pacific beetle cockroach, Diploptera punctata, has proven to be a valuable model insect in the study of the dynamics regulating juvenile hormone (JH) biosynthesis and metabolism, particularly during late nymphal development and reproduction. This stems in part from its unusual mode of reproduction, adenotrophic viviparity, in which females give birth to live young that have been nourished throughout embryonic development by a protein-rich 'milk' secreted by the wall of the brood sac or uterus. In this animal, as in most insects, JH regulates both vitellogenin production and its uptake by developing oocytes.

Fine structure of corpora allata of castes with different rates of juvenile hormone production in the termite Reticulitermes flavipes.

The aim of this work is to describe corpora allata (CA) of several castes of the termite Reticulitermes flavipes that have different rates of juvenile hormone (JH) synthesis, with respect to differences in fine structure, volume, and intensity of allatostatin immunoreactivity in their innervation. The castes chosen are workers and their potential derivatives, apterous secondary reproductives and pre-soldiers (the precursors of soldiers). These castes, at the stages chosen, produce JH at low, high and intermediate rates respectively.