Genetic Analysis of Egyptian Date (<Emphasis Type="Italic">Phoenix dactylifera</Emphasis> L.) Accessions Using AFLP Markers

Forty-seven samples of date palm (Phoenix dactylifera L.) collected from eight locations in Egypt were studied using four sets of amplified fragment length polymorphism (AFLP) markers with near infrared fluorescence labeled primers. These samples belonged to 21 named accessions and 9 of unknown pedigrees. A total of 350 bands were scored and 233 (66.6%) were polymorphic. Twenty-seven Egyptian accessions and ‘Medjool’and ‘Deglet Noor’accessions from California could beclassified into the major cluster. This major cluster may represent a major group of date palm germplasm in North Africa. There were four other clusters, each containing one or two accessions. The variety ‘Halawy’and one accession of unknown provenance were most likely from hybridization between two clusters. Six groups of accessions of which had the same names, revealed similar but not identical AFLP profiles suggesting these accessions might derive from seedlings rather thanthrough clonal offshoot propagation.     

Identification of Mulberry Dwarf Phytoplasmas in the Genital Organs and Eggs of Leafhopper Hishimonoides sellatiformis

ABSTRACT The presence of mulberry dwarf (MD) phytoplasmas in organs of the inoculative vector insects Hishimonoides sellatiformis and Hishimonus sellatus was determined by means of electron microscopy (EM) and polymerase chain reaction (PCR) assays. Many MD phytoplasmas were detected in genital organs as well as in the intestines, salivary glands, brains, fat bodies, and thoracic ganglia of Hishimonoides sellatiformis, but only in the intestine and salivary glands of Hishimonus sellatus. Many phytoplasmas with characteristic morphology were observed via EM in ovaries, seminal receptacles, and testes, and they were further identified by PCR assays with group I-specific primers. In addition, the organisms were detected by direct or nested PCR assays in eggs (head pigmentation stage of embryos) laid on mulberry shoots by inoculative leafhoppers and in the newly hatched nymphs from these eggs. These findings indicate that transovarial transmission of MD phytoplasmas occurs in Hishimonoides sellatiformis.     

High-throughput mapping of a dynamic signaling network in mammalian cells

Signaling pathways transmit information through protein interaction networks that are dynamically regulated by complex extracellular cues. We developed LUMIER (for luminescence-based mammalian interactome mapping), an automated high-throughput technology, to map protein-protein interaction networks systematically in mammalian cells and applied it to the transforming growth factor-beta (TGFbeta) pathway. Analysis using self-organizing maps and k-means clustering identified links of the TGFbeta pathway to the p21-activated kinase (PAK) network, to the polarity complex, and to Occludin, a structural component of tight junctions. We show that Occludin regulates TGFbeta type I receptor localization for efficient TGFbeta-dependent dissolution of tight junctions during epithelial-to-mesenchymal transitions.