Publications by authors named "Karolyn F Buttle"

This study provides evidence for the Golgi-like activity of the multilayered interlaced network (MIN) and new ultrastructural observations of the MIN in the sporoplasm of Anncaliia algerae, a microsporidium that infects both insects and humans. The MIN is attached to the end of the polar tubule upon extrusion from the germinating spore. It surrounds the sporoplasm, immediately below its plasma membrane, and most likely maintains the integrity of the sporoplasm, as it is pulled through the everting polar tube.

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The C. elegans eat-3 gene encodes a mitochondrial dynamin family member homologous to Opa1 in humans and Mgm1 in yeast. We find that mutations in the C.

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The role of mitochondria in cell metabolism and survival is controlled by calcium signals that are commonly transmitted at the close associations between mitochondria and endoplasmic reticulum (ER). However, the physical linkage of the ER-mitochondria interface and its relevance for cell function remains elusive. We show by electron tomography that ER and mitochondria are adjoined by tethers that are approximately 10 nm at the smooth ER and approximately 25 nm at the rough ER.

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Mitochondrial encephalomyopathies are common and devastating multisystem genetic disorders characterized by neuromuscular dysfunction and tissue degeneration. Point mutations in the human mitochondrial ATP6 gene are known to cause several related mitochondrial disorders: NARP (neuropathy, ataxia, and retinitis pigmentosa), MILS (maternally inherited Leigh's syndrome), and FBSN (familial bilateral striatal necrosis). We identified a pathogenic mutation in the Drosophila mitochondrial ATP6 gene that causes progressive, adult-onset neuromuscular dysfunction and myodegeneration.

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Sporozoites of the apicomplexan Cryptosporidium parvum possess a small, membranous organelle sandwiched between the nucleus and crystalloid body. Based upon immunolabelling data, this organelle was identified as a relict mitochondrion. Transmission electron microscopy and tomographic reconstruction reveal the complex arrangement of membranes in the vicinity of this organelle, as well as its internal organization.

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Mitochondria of human Leydig cells were reconstructed in three dimension utilizing the technique of electron microscopic tomography to obtain a better understanding of the topology of the internal membrane system and the relationship of these cristae to the inner boundary membrane (IBM). Cristae structure, in many respects, is consistent with previous tomographic studies from typical mitochondria, i.e.

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