Project description:Copper (Cu) is not only one of the essential trace elements for animal body, but also an important nutrient component for normal physiology and metabolism of animal reproductive system. Lack or excess of copper will directly or indirectly affect animal reproductive activities. However, the effect of copper on reproductive performance of boars and sows has not been studied and the effect of excessive Copper addition on reproductive performance of sows is even less, and the molecular mechanism is poorly understood. Here, we document that copper has the negative effects on the oocyte maturation and Organelle function. We show that copper exposure perturbs the porcine oocyte meiotic maturation and impair the spindle/chromosome structure, displaying an obviously defective spindle assembly, and abnormal distribution of actin dynamics and cortical granules. In addition, single-cell transcriptome analysis identifies target effectors of copper in porcine oocytes, which was further demonstrated that copper exposure affects the distribution and function of mitochondria, and high ROS levels, DNA damage, and early apoptosis in porcine oocytes. Collectively, we demonstrate that copper exposure causes abnormalities in mitochondrial function and distribution, resulting in increased oxidative stress ROS levels, DNA damage and apoptosis, ultimately leading to decreased quality of porcine oocytes.
Project description:Copper-limiting growth conditions were thought to cause an induction of genes possibly involved in copper uptake and sorting. This rationale in mind, we performed microarray analyses on B. japonicum cells grown in three variations of the BVM minimal medium. Variant 1 contained 2 μM CuSO4 (copper excess). Variant 2 was prepared in HCl-treated glassware without any copper added (copper starvation). The residual copper concentration in this copper-starvation medium was analyzed by GF-AAS and determined to be 5 nM. Variant 3 (extreme copper limitation) was prepared like variant 2 but with the addition of 10 μM BCS and 1 mM ascorbic acid where BCS chelates Cu(I) selectively, and ascorbic acid reduces any Cu(II) to Cu(I). Changes in the transcription profiles were recorded by the pairwise comparison of cells grown in variant 2 vs. 1, and variant 3 vs. 2. Only a small set of genes were differentially up- or down-regulated when copper-starved cells were compared with cells grown in copper excess. Most notably, five genes located adjacent to each other on the B. japonicum genome displayed an increased expression: bll4882 to bll4878. The five genes were named pcuA, pcuB, pcuC, pcuD, and pcuE (mnemonic of proteins for Cu trafficking). The genes with decreased expression are either of unknown function or – not surprisingly – play a role in copper resistance. Extreme copper limitation (variant 3 vs. 2) did not further enhance the expression of the five pcu genes. Instead, another cluster of adjacent genes was strongly up-regulated: bll0889 to bll0883, which code for unidentified transport functions. Incidentally, the list also includes the copper chaperone ScoI. Taken together, copper-limiting growth conditions have led to the de-repression of genes potentially involved in copper acquisition.
Project description:Copper-limiting growth conditions were thought to cause an induction of genes possibly involved in copper uptake and sorting. This rationale in mind, we performed microarray analyses on B. japonicum cells grown in three variations of the BVM minimal medium. Variant 1 contained 2 M-NM-<M CuSO4 (copper excess). Variant 2 was prepared in HCl-treated glassware without any copper added (copper starvation). The residual copper concentration in this copper-starvation medium was analyzed by GF-AAS and determined to be 5 nM. Variant 3 (extreme copper limitation) was prepared like variant 2 but with the addition of 10 M-NM-<M BCS and 1 mM ascorbic acid where BCS chelates Cu(I) selectively, and ascorbic acid reduces any Cu(II) to Cu(I). Changes in the transcription profiles were recorded by the pairwise comparison of cells grown in variant 2 vs. 1, and variant 3 vs. 2. Only a small set of genes were differentially up- or down-regulated when copper-starved cells were compared with cells grown in copper excess. Most notably, five genes located adjacent to each other on the B. japonicum genome displayed an increased expression: bll4882 to bll4878. The five genes were named pcuA, pcuB, pcuC, pcuD, and pcuE (mnemonic of proteins for Cu trafficking). The genes with decreased expression are either of unknown function or M-bM-^@M-^S not surprisingly M-bM-^@M-^S play a role in copper resistance. Extreme copper limitation (variant 3 vs. 2) did not further enhance the expression of the five pcu genes. Instead, another cluster of adjacent genes was strongly up-regulated: bll0889 to bll0883, which code for unidentified transport functions. Incidentally, the list also includes the copper chaperone ScoI. Taken together, copper-limiting growth conditions have led to the de-repression of genes potentially involved in copper acquisition. Microarray-based transcriptome analysis of B. japonicum 110spc4 wild-type cells grown under normal, copper-limiting and copper excess conditions
Project description:Biogenesis of complex IV of the mitochondrial respiratory chain requires assembly factors for subunit maturation, co-factor attachment and stabilization of intermediate assemblies. A pathogenic mutation in Coa6, leading to substitution of a conserved tryptophan to a cysteine residue, results in a loss of complex IV activity and cardiomyopathy. Here we demonstrate that the complex IV defect correlates with a severe loss in complex IV assembly in patient heart but not fibroblasts. Complete loss of Coa6 activity using gene-editing in HEK293T cells resulted in a profound growth defect due to complex IV deficiency, caused by impaired biogenesis of the copper-bound mtDNA encoded subunit COX2 and subsequent accumulation of complex IV assembly intermediates. We show that the pathogenic mutation in Coa6 does not affect its import into mitochondria but impairs its maturation and stability. Furthermore we find that Coa6 binds copper with a high affinity and also associates with mitochondrial copper chaperones, revealing that Coa6 is intricately involved in the copper-dependent biogenesis of COX2.
Project description:Cytochrome c oxidase assembly factor 7 (COA7) is a metazoan-specific assembly factor, critical for the biogenesis of mitochondrial complex IV (cytochrome c oxidase). Although mutations in COA7 have been linked to complex IV assembly defects and neurological conditions such as peripheral neuropathy, ataxia and leukoencephalopathy, the precise role COA7 plays in the biogenesis of complex IV is not known. Here we show that the absence of COA7 leads to arrest of the complex IV assembly pathway after the initial step where the COX1 module is built, progression from which requires the incorporation of copper, through the biogenesis of the CuA site. The crystal structure of COA7, determined to 2.4 Å resolution, reveals a ‘banana-shaped’ molecule composed of five helix-turn-helix repeats, tethered by disulfide bonds. We find that in solution, purified COA7 binds heme with micromolar affinity, through axial ligation to the central iron atom by histidine and methionine residues. COA7 interacts transiently with the copper metallochaperones SCO1 and SCO2 that function in copper delivery to COX2 and catalyzes the reduction of disulfide bonds within these proteins, which constitute the protein copper binding sites. We therefore propose that COA7 is a heme-binding disulfide reductase that acts in the biogenesis of the CuA site, that underpins complex IV assembly.
Project description:A 3 x 2 factorial design was used to elucidate the genome-wide transcriptional response to the deletion of yeast ortholog of Wilson and Menkes disease causing gene; CCC2, at changing copper levels. Homozygous deletion mutant of CCC2, which encodes Cu+2 transporting P-type ATPase required to export copper from the cytosol into the extracytosolic compartment, and the reference strain were cultivated in fully controlled fermenters in duplicates in glucose-rich defined medium containing three different levels of copper. The three different copper concentrations were selected such that; copper deficient condition, which was prepared by excluding the CuSO4.7H2O from the defined medium, low copper or adequate copper concentration, which is the standard amount of copper in defined medium (0.04 ?M) and high copper concentration (0.5 mM), which was able to restore respiration deficiency in ccc2?/ccc2? strain.