title: Proteome analysis during pod, zygotic and somatic embryo maturation of Theobroma cacao.
abstract: Two dimensional electrophoresis and nano-LC-MS were performed in order to identify alterations in protein abundance that correlate with maturation of cacao zygotic and somatic embryos. The cacao pod proteome was also characterized during development. The recently published cacao genome sequence was used to create a predicted proteolytic fragment database. Several hundred protein spots were resolved on each tissue analysis, of which 72 variable spots were subjected to MS analysis, resulting in 49 identifications. The identified proteins represent an array of functional categories, including seed storage, stress response, photosynthesis and translation factors. The seed storage protein was strongly accumulated in cacao zygotic embryos compared to their somatic counterpart. However, sucrose treatment (60 g L(-1)) allows up-regulation of storage protein in SE. A high similarity in the profiles of acidic proteins was observed in mature zygotic and somatic embryos. Differential expression in both tissues was observed in proteins having high pI. Several proteins were detected exclusively in fruit tissues, including a chitinase and a 14-3-3 protein. We also identified a novel cacao protein related to known mabinlin type sweet storage proteins. Moreover, the specific presence of thaumatin-like protein, another sweet protein, was also detected in fruit tissue. We discuss our observed correlations between protein expression profiles, developmental stage and stress responses.
authors.affiliation: Laboratory of Plant Physiology, Department of Biological Science, Higher Teachers Training College, University of Yaounde I, P.O. Box 47, Yaounde, Cameroon. Electronic address: niemenak@yahoo.com.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Niemenak
authors.affiliation: Proteomics and Mass Spectrometry Core Facility, the Huck Institutes of the Life Sciences, Penn State University, University Park, PA 16802, USA.
authors.forename: Edward
authors.initials: E
authors.lastname: Kaiser
authors.affiliation: The Pennsylvania State University, Department of Plant Science and the Huck Institutes of the Life Sciences, University Park, Pennsylvania, PA 16802, USA.
authors.forename: Siela N
authors.initials: SN
authors.lastname: Maximova
authors.affiliation: Proteomics and Mass Spectrometry Core Facility, the Huck Institutes of the Life Sciences, Penn State University, University Park, PA 16802, USA.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Laremore
authors.affiliation: The Pennsylvania State University, Department of Plant Science and the Huck Institutes of the Life Sciences, University Park, Pennsylvania, PA 16802, USA.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Guiltinan
mesh_terms: D002099:Cacao / Q000196:embryology* / Q000235:genetics / Q000378:metabolism*; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D013058:Mass Spectrometry; D036103:Nanotechnology; D010940:Plant Proteins / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D012639:Seeds / Q000235:genetics / Q000378:metabolism*; D015053:Zygote / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D020543:Proteome
keywords: Cacao pod; Embryogenesis; Maturation; Proteomics; Theobroma cacao