In 1935, Shiro Akabori began research on the preparation of taka-amylase A with a purity suitable for chemical research, with the intention of elucidating the chemical nature of the enzyme. He succeeded in developing a method to efficiently obtain crystallized taka-amylase A from Aspergillus oryzae. Using crystallized taka-amylase A as the starting material, a series of studies were conducted to determine its amino acid composition and sequence, sugar chain structure, and three-dimensional structure. Based on these results, the molecular structure and catalytic mechanism of taka-amylase A were elucidated. The scientific achievements from research on taka-amylase A significantly enhanced Japan’s capabilities in protein research, represented by the fact that taka-amylase A was the first amylase in the world for which both chemical and crystallographic structures were elucidated.
K. Shibata is the ancestor of the research on anthocyanins in Japan and proposed metal complex theory against the pH theory by R. Willstätter. Shibata’s successors, S. Hattori and K. Hayashi, made efforts to clarify blue flower coloration by metal complexation and found commelinin, a self-assembled supramolecular metal complex pigment, in blue dayflower, Tsuyukusa. The author introduces two key reports on blue flower coloration published in the Proceedings of the Japan Academy and describes the subsequent development of the study.
This review describes the development of evolutionary studies of sex based on the volvocine lineage of green algae, which was facilitated by whole-genome analyses of both model and non-model species. Volvocine algae, which include Chlamydomonas and Volvox species, have long been considered a model group for experimental studies investigating the evolution of sex. Thus, whole-genomic information on the sex-determining regions of volvocine algal sex chromosomes has been sought to elucidate the molecular genetic basis of sex evolution. By 2010, whole genomes were published for two model species in this group, Chlamydomonas reinhardtii and Volvox carteri. Recent improvements in sequencing technology, particularly next-generation sequencing, allowed our studies to obtain complete genomes for non-model, but evolutionary important, volvocine algal species. These genomes have provided critical details about sex-determining regions that will contribute to our understanding of the diversity and evolution of sex.
Nonhuman primates, particularly macaque and marmoset monkeys, serve as invaluable models for studying complex brain functions and behavior. However, the lack of suitable genetic neuromodulation tools has constrained research at the network level. This review examines the application of a chemogenetic technology, specifically, designer receptors exclusively activated by designer drugs (DREADDs), to nonhuman primates. DREADDs offer a means of reversibly controlling neuronal activity within a specific cell type or neural pathway, effectively targeting multiple brain regions simultaneously. The combination of DREADDs with imaging techniques, such as positron emission tomography and magnetic resonance imaging, has significantly enhanced nonhuman primate research, facilitating the precise visualization and manipulation of specific brain circuits and enabling the detailed monitoring of changes in network activity, which can then be correlated with altered behavior. This review outlines these technological advances and considers their potential for enhancing our understanding of primate brain circuit function and developing novel therapeutic approaches for treating brain diseases.