Studies on cell division traditionally focus on the mechanisms of chromosome segregation and cytokinesis, yet we know comparatively little about how organelles segregate. Analysis of organelle partitioning in asymmetrically dividing cells has provided insights into the mechanisms through which cells control organelle distribution. Interestingly, these studies have revealed that segregation mech...

Chloroplasts and their nonphotosynthetic relatives in the plastid organelle family evolved from a cyanobacterial endosymbiont (for review, see Timmis et al., 2004). The subsequent coevolution of the chloroplast and nuclear genomes produced an organelle that is eubacterial at its core but with extensive chloroplastspecific embellishments. Of the thousands of genes in the cyanobacterial ancestor,...

multipotent skin-derived stem cell, and a purified neural stem cell from the brain have come on the scene at a delicate time in the debate over embryonic stem cell research. Each success in isolating adult stem cells, such as these cells, gives ammunition to opponents of embryonic stem cell research, who point to adult-derived stem cells as an alternative source of transplant-ready material. Th...

considering its central role in energy metabolism in almost all eukaryotes, the mitochondrion is an amazingly plastic organelle, both evolutionarily and functionally. the few genes that the mitochondrial genome (mito chondrial DNa; mtDNa) encodes are clearly bacterial in origin —emanating from the α-proteobacterial lineage—supporting the widely held view that the mitochondrion is the evolutiona...

To efficiently utilize the growing body of available protein localization data, we have developed Organelle DB, a web-accessible database cataloging more than 25,000 proteins from nearly 60 organelles, subcellular structures and protein complexes in 154 organisms spanning the eukaryotic kingdom. Organelle DB is the first on-line resource devoted to the identification and presentation of eukaryo...

Volvocalean green algae have among the most diverse mitochondrial and plastid DNAs (mtDNAs and ptDNAs) from the eukaryotic domain. However, nearly all of the organelle genome data from this group are restricted to unicellular species, like Chlamydomonas reinhardtii, and presently only one multicellular species, the ∼4,000-celled Volvox carteri, has had its organelle DNAs sequenced. The V. carte...

The metabolism of lipid-soluble drugs and chemicals by the endoplasmic reticulum mixed function oxidase in liver slices or hepatic microsomes, the latter in the presence of mitochondria, was stimulated up to 80% by succinate and was inhibited up to 30% by oxalacetate. When the combined organelles were used, maximal effects were obtained at 4 to 5 times more mitochondrial protein than microsomal...

The intricate and essential process of the enzymatic translation of the genetic information, encoded in mRNA into proteins, is performed by the universal cellular organelle, the ribosome. Ribosomes from all organisms are assemblies of several strands of RNA and many different proteins. These components are arranged in two subunits of unequal size, which associate upon initiation of protein synt...

What controls the dynamics of the transitional ER? Secretory proteins exit from the endoplasmic reticulum (ER) at specialized transitional ER (tER) sites. Benjamin Glick (University of Chicago) described the role of Sec16 in regulating tER organization in the yeast Pichia pastoris. Membrane-associated Sec16 seems to slow ER export. A mutation that redistributes Sec16 to the cytosol relieves thi...