24 research outputs found
Reduction of the ATPase inhibitory factor 1 (IF1) leads to visual impairment in vertebrates
In vertebrates, mitochondria are tightly preserved energy producing organelles, which sustain nervous system development and function. The understanding of proteins that regulate their homoeostasis in complex animals is therefore critical and doing so via means of systemic analysis pivotal to inform pathophysiological conditions associated with mitochondrial deficiency. With the goal to decipher the role of the ATPase inhibitory factor 1 (IF1) in brain development, we employed the zebrafish as elected model reporting that the Atpif1aâ/â zebrafish mutant, pinotage (pnttq209), which lacks one of the two IF1 paralogous, exhibits visual impairment alongside increased apoptotic bodies and neuroinflammation in both brain and retina. This associates with increased processing of the dynamin-like GTPase optic atrophy 1 (OPA1), whose ablation is a direct cause of inherited optic atrophy. Defects in vision associated with the processing of OPA1 are specular in Atpif1â/â mice thus confirming a regulatory axis, which interlinks IF1 and OPA1 in the definition of mitochondrial fitness and specialised brain functions. This study unveils a functional relay between IF1 and OPA1 in central nervous system besides representing an example of how the zebrafish model could be harnessed to infer the activity of mitochondrial proteins during development
Paleontology of leaf beetles
`The rate of evolution in any large group is not uniform; there are periods of relatise stability, and periods of comparatively rapid change.' Cockerell and LeVeque, 1931 To Yenli Ych, my beloved wife, a most wonderful person! The fossil record of the Chrysomelidae can be tentatively traced back to the late Paleozoic to early Mesozoic Triassic. Mesozoic records at least 9 subfamilies, 19 genera, and 35 species, are represented by the Sagrinae, the exclusively Mesozoic Proto scelinae, Clytrinae, Cryptocephalinae, Eumolpinae, Chrysomelinae. Galerucinac, Alticinae, and Cassidinae. Cenozoic records at least 12 subfamilies- 63 % of the extant- 12! genera, and 325 species, include the same extant subfamilies as well as the Donaciinae, Zeugophorinae, Criocerinae, and Hispinae and can be frequently identified to genus, especially if preserved in amber. Quaternary records are often identified to extant species. tn total, at least t3! genera about 4 % of total extant, and 357 species < 1 % have been reported. At least, 24 genera <1 % of the extant seem to be extinct. Although reliable biological information associated with the fossil chrysomelids is very scarce, it seems that most of the modern host-plant associations were established, at least, in the late Mesozoic to early Cenozoic. As a whole, stasis seems to be the general rule of the chrysomelid fossil record. Together with other faunal elements, chrysomelids, especially donaciines, have been used as biogeographic and paleoclimatological indicators in the Holocene. I
Correction of CFTR function in nasal epithelial cells from cystic fibrosis patients predicts improvement of respiratory function by CFTR modulators
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Expression, Purification, Structural and Functional Analysis of SycB: A Type Three Secretion Chaperone From Yersinia Enterocolitica
In Yersinia enterocolitica biovar 1B, a genome
encoded TTSS designated as Ysa-Ysp system is used for
virulence. SycB is an annotated chaperone to this system.
SycB is soluble in presence of translocator YspC. SycB and
its truncated form (DSycB(1â114)) exist as dimers. YspC
forms a 1:1 complex with SycB. Homology model of SycB
shows a flexible N-terminal may be required for solubility
and dimerization; and concave core formed by antiparallel
helices of TPRs. Far UV CD spectra confirm that SycB is
predominantly alpha helical. Near UV CD spectra show that
SycB has tertiary structure at pH 7.2 (native folded protein),
which disappears at pH 5 (molten globule) and SycB
releases YspC at pH 5. SycB has a cooperative melting
behavior. At pH 7.2, SycB shows solvent accessible
hydrophobic patches. Concave core in the model exhibits
ANS binding within FRET distance of tyrosines in the TPR,
allowing a range of interaction of SycB with its ligand