Development: How the Reissner Fiber Keeps Our Back Straight

Abstract

Two new studies elegantly identify a missing link between idiopathic scoliosis and the Reissner fiber.

Diversity and Function of Motile Ciliated Cell Types within Ependymal Lineages of the Zebrafish Brain

“…It remains to be understood whether this difference in hydrocephalus prevalence among species relates to differences in susceptibility to stenosis of the aqueduct, in overall CSF dynamics and/or in additional genetic predisposition. Additionally, defects in motile cilia have been associated with scoliotic malformations of the spine in zebrafish, at larval, juvenile and adult stages [19,34,35,72,94,95]. We did not observe scoliosis in foxj1b, gmnc, as well as foxj1a+/-;foxj1b-/-and foxj1b;gmnc mutant animals, suggesting that body axis formation is not regulated by the ciliary mechanisms described in this work.…”

Resolving primary pathomechanisms driving idiopathic-like spinal curvature using a new katnb1 scoliosis model

“…Therefore, CSF flow defects and scoliosis in katnb1 mh102/mh102 mutants are not associated with loss of RF formation, albeit may involve decreased functionality or aberrant aggregation of Reissner's substance. These observations challenge current theories regarding the etiopathogenesis of scoliosis (see Bagnat and Gray, 2020;Ringers and Jurisch-Yaksi, 2020), demonstrating that the presence of RF is not sufficient to keep the spine straight. Rather, the specific and ectopic accumulation of Sspo below the forebrain and rhombencephalic ChPs suggests that the primary defect in katnb1 IS models relates to abnormal ChP development and/or function with correlative Sspo accumulation subsequent to onset of curvature.…”

Diversity and function of motile ciliated cell types within ependymal lineages of the zebrafish brain

“…It remains to be understood whether this difference in hydrocephalus prevalence among species relates to differences in susceptibility to aqueduct stenosis, the degree of cilia loss in the different conditions, overall CSF dynamics, and/or in additional genetic predisposition. Additionally, defects in motile cilia have been associated with scoliotic malformations of the spine in zebrafish at larval, juvenile, and adult stages ( Grimes et al., 2016 ; Ringers and Jurisch-Yaksi, 2020 ; Zhang et al., 2018 ; Cantaut-Belarif et al., 2018 ; Vesque et al., 2019 ; Bearce and Grimes, 2021 ). We did not observe scoliosis in foxj1b and gmnc , as well as foxj1a+/−;foxj1b−/− and foxj1b;gmnc , mutant animals, suggesting that spine morphogenesis may rely primarily on foxj1a .…”