Article reviewing blood-brain barriers (BBBs) in their various forms in both invertebrates and vertebrates, with an emphasis on the function, evolution, and conditional relevance of popular animal models such as the fruit fly and the zebrafish to mammalian BBB research.

This article is the fourth paper of the Special Issue Memory and Criticality. It bridges the the theoretical debate on the role of memory and criticality discussed in the three earlier manuscripts, with a review of key concepts in biology and focus on cell-to-cell communication in organismal development. The authors suggest that in conjunction with morphogenetic gradients, there exist gradients of information transfer creating cybernetic loops of stability and disorder, setting the stage for adaptive capability. Criticality, therefore, appears to be an important factor in the transmission, transfer and coding of information for complex adaptive system development.

This article is an editorial on the research topic Microbial C1 Metabolism and Biotechnology. This special topic presents studies focused on the fundamental aspects of C1 metabolism in diverse microbial systems with the ability to convert anthropogenic greenhouse gases into valuable products.

Article showing that a recently identified protein termed LD-associated protein [LDAP]-interacting protein (LDIP) works together with both endoplasmic reticulum-localized SEIPIN and the LD-coat protein LDAP to facilitate LD formation in Arabidopsis thaliana. The data is discussed in the context of a new model for LD biogenesis in plant cells with evolutionary connections to LD biogenesis in other eukaryotes.

Article that provides a brief overview of current research on synthetic biology and metabolic engineering approaches to control phenylpropanoid synthesis and phenylpropanoid-related biosensors, advocating for the use of biosensors and genetic circuits as a step forward in plant synthetic biology to develop autonomously-controlled phenylpropanoid-producing plant biofactories.