scholarly journals The evolutionary origins of antagonistic neurotrophin signaling

2017 ◽  
Vol 216 (5) ◽  
pp. 1223-1225 ◽  
Author(s):  
Austin B. Keeler ◽  
Christopher D. Deppmann
Keyword(s):  
Nervous System ◽  
Effector Proteins ◽  
Competitive Balance ◽  
Form And Function ◽  
Evolutionary Origins ◽  
Survival Pathways ◽  
Toll Receptor ◽  
And Function ◽  
Neurotrophin Signaling ◽  
Receptor Family

A competitive balance between constructive and destructive developmental cues governs both the form and function of the vertebrate nervous system. In this issue, Foldi et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201607098) explore the evolutionary origins of these cues and report that in Drosophila melanogaster pro- and mature neurotrophins are capable of inducing death and survival pathways, respectively, by binding Toll receptor family members, which then recruit distinct sets of effector proteins.

scholarly journals Further twists in gastropod shell evolution

2008 ◽  
Vol 4 (2) ◽  
pp. 179-182 ◽  
Author(s):  
Reuben Clements ◽  
Thor-Seng Liew ◽  
Jaap Jan Vermeulen ◽  
Menno Schilthuizen
Keyword(s):  
Evolutionary Biology ◽  
Logarithmic Spiral ◽  
Spiral Growth ◽  
Evolutionary Perspective ◽  
Gastropod Shell ◽  
Form And Function ◽  
Evolutionary Origins ◽  
Taxonomic Groups ◽  
And Function ◽  
Shell Coiling

The manner in which a gastropod shell coils has long intrigued laypersons and scientists alike. In evolutionary biology, gastropod shells are among the best-studied palaeontological and neontological objects. A gastropod shell generally exhibits logarithmic spiral growth, right-handedness and coils tightly around a single axis. Atypical shell-coiling patterns (e.g. sinistroid growth, uncoiled whorls and multiple coiling axes), however, continue to be uncovered in nature. Here, we report another coiling strategy that is not only puzzling from an evolutionary perspective, but also hitherto unknown among shelled gastropods. The terrestrial gastropod Opisthostoma vermiculum sp. nov. generates a shell with: (i) four discernable coiling axes, (ii) body whorls that thrice detach and twice reattach to preceding whorls without any reference support, and (iii) detached whorls that coil around three secondary axes in addition to their primary teleoconch axis. As the coiling strategies of individuals were found to be generally consistent throughout, this species appears to possess an unorthodox but rigorously defined set of developmental instructions. Although the evolutionary origins of O. vermiculum and its shell's functional significance can be elucidated only once fossil intermediates and live individuals are found, its bewildering morphology suggests that we still lack an understanding of relationships between form and function in certain taxonomic groups.

scholarly journals On a bender—BARs, ESCRTs, COPs, and finally getting your coat

2011 ◽  
Vol 193 (6) ◽  
pp. 963-972 ◽  
Author(s):  
Mark C. Field ◽  
Andrej Sali ◽  
Michael P. Rout
Keyword(s):  
Comparative Genomics ◽  
Protein Complexes ◽  
Eukaryotic Cell ◽  
Intracellular Membrane ◽  
Membrane Systems ◽  
Profound Impact ◽  
Form And Function ◽  
Evolutionary Origins ◽  
And Function ◽  
Internal Architecture

Tremendous variety in form and function is displayed among the intracellular membrane systems of different eukaryotes. Until recently, few clues existed as to how these internal membrane systems had originated and diversified. However, proteomic, structural, and comparative genomics studies together have revealed extensive similarities among many of the protein complexes used in controlling the morphology and trafficking of intracellular membranes. These new insights have had a profound impact on our understanding of the evolutionary origins of the internal architecture of the eukaryotic cell.

Form and Function of Facial Expressive Origins

2017 ◽  
Author(s):  
Daniel H. Lee ◽  
Adam K. Anderson
Keyword(s):  
Facial Expressions ◽  
Social Communication ◽  
Visual Information ◽  
Mental States ◽  
Form And Function ◽  
Evolutionary Origins ◽  
Functional Perspective ◽  
Sensory Effects ◽  
And Function ◽  
Communicative Role

Facial expressions are an important source of social communication. But we do not know why they appear the way they do and how they arose. Here we discuss evidence supporting Darwin’s theory that our expressions originated for sensory egocentric function for the expresser, which were then co-opted as signals for allocentric social function. We show that facial expressions of fear and disgust have distinct opposing sensory effects that serve each emotion’s theorized function, regulating the intake of nasal and visual information. Then, we show how such egocentrically adaptive expressive forms may have been socially co-opted for allocentric function, transmitting basic gaze signals and complex mental states adaptively congruent for the receiver as the expresser. Together, the evidence connects the appearance of our expressions from their evolutionary origins to their modern-day communicative role, providing a functional perspective for organizing and understanding expression forms.

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