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WOS: 000458101700001 PubMed ID: 30730291 Comparative analyses of neuronal phenotypes in closely related species can shed light on neuronal changes occurring during evolution. The study of post-mortem brains of nonhuman primates (NHPs) has been limited and often does not recapitulate important species-specific developmental hallmarks. We utilize induced pluripotent stem cell (iPSC) technology to investigate the development of cortical pyramidal neurons following migration and maturation of cells grafted in the developing mouse cortex. Our results show differential migration patterns in human neural progenitor cells compared to those of chimpanzees and bonobos both in vitro and in vivo, suggesting heterochronic changes in human neurons. The strategy proposed here lays the groundwork for further comparative analyses between humans and NHPs and opens new avenues for understanding the differences in the neural underpinnings of cognition and neurological disease susceptibility between species. National Institutes of Health; California Institute for Regenerative Medicine; National Alliance for Research on Schizophrenia and Depression; Leona M. and Harry B. Helmsley Charitable Trust; Salk Cancer Center [NCI P30 CA014195] National Institutes of Health Research Project Grant Maria C Marchetto Alysson R Muotri Krishnan Padmanabhan Fred H Gage; California Institute for Regenerative Medicine Research Grant Alysson R Muotri; National Institutes of Health Pathway to independence award Krishnan Padmanabhan; National Alliance for Research on Schizophrenia and Depression Young Investigator award Krishnan Padmanabhan; Leona M. and Harry B. Helmsley Charitable Trust Research Project Grant Fred H Gage Salk Cancer Center NCI P30 CA014195 Fred H Gage; The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Publisher Summary This chapter discusses epitope tagging for the detection of fusion protein expression in transgenic plants. The chapter describes the development of the c-myc epitope tag system for the detection of transprotein expression in transgenic tobacco plants. An expression vector for plant c-myc epitope tagging was constructed and introduced into tobacco plants via Agrobacterium -mediated transformation. The results show that c-myc epitope tagged trans-protein can be detected in extracts from as little as 5 mg of leaf tissue. The Mycl-9El0 monoclonal antibody shows no cross-reactivity to endogenous tobacco or Arabidopsis thaliana proteins. In addition, the antibody can be used to localize expression in various tissues using the tissue print method. The ability of the Mycl-9E10 antibody to detect the 10-amino acid c-myc epitope on Westerns blots and tissue prints and the absence of antibody cross reactivity to endogenous tobacco and Arabidopsis proteins make this epitope–antibody pair an excellent choice as a general marker for protein expression in transgenic plants.

Enzymes catalyzing the first and last steps in cocoa butter biosynthesis were studied in microsomal preparations from developing cocoa seeds. Both the acyl-CoA:sn-glycerol-3-phosphate 0-acyltransferase (EC 2.3.1.15) and the acyl-CoA:1,2-diacylglycerol 0-acyltransferase (EC 2.3.1.20) showed broad specificity for three fatty acid donors (palmitoyl-CoA, stearoyl-CoA and oleoyl-CoA), but the relative amounts of incorporation of these fatty acids into lysophosphatidic acid and triacylglycerol were influenced by temperature of incubation. The selectivities of the two acyltransferases for saturated vs unsaturated acyl-CoA’s also were investigated over a range of temperatures. The data indicate that, in general, the ratio of saturated to unsaturated fatty acids incorporated into glycerol esters increases with increasing temperature of incubation, consistent with the hypothesis that temperature effects on these enzymes contribute to the phenomenon of “soft” cocoa butter, i.e., that cocoa butter obtained from seeds grown in cooler climates has a lower melting point than that prepared from seeds grown in warmer climates.

Triacylglycerols make up about 96% of mature cocoa (Theobroma cacao) seed lipid, more than half the seed dry weight, and thus are the major storage products of the seed. These storage products are a mixture of glycerol esters of oleic, palmitic, stearic, and much smaller amounts of linoleic acid. The collection of esters is called cocoa butter, a solid fat, and, at more than $4 a pound, is the most expensive edible fat in the world. Annual world production of cocoa butter is more than 2 billion pounds.