A disc-electrophoresis investigation of certain characteristics of Triton X-100 solubilized proteins from malePeriplaneta americana

Resumen Un agregado de proteínas solubilizadas en Triton X-100 fue resuelto como una banda por electroforesis a un pH de 8.5. En un pH de 7.1 estas fracciones no demuestran el efecto de agregación. Solamente electroforesis conTris/glicina como amortiguador y concentraciones del detergente menor de 0.6% dieron resultados.     

Jelly belly protein activates the receptor tyrosine kinase Alk to specify visceral muscle pioneers

The secreted protein Jelly belly (Jeb) is required for an essential signalling event in Drosophila muscle development. In the absence of functional Jeb, visceral muscle precursors are normally specified but fail to migrate and differentiate. The structure and distribution of Jeb protein implies that Jeb functions as a signal to organize the development of visceral muscles. Here we show that the Jeb receptor is the Drosophila homologue of anaplastic lymphoma kinase (Alk), a receptor tyrosine kinase of the insulin receptor superfamily. Human ALK was originally identified as a proto-oncogene, but its normal function in mammals is not known. In Drosophila, localized Jeb activates Alk and the downstream Ras/mitogen-activated protein kinase cascade to specify a select group of visceral muscle precursors as muscle-patterning pioneers. Jeb/Alk signalling induces the myoblast fusion gene dumbfounded (duf; also known as kirre) as well as org-1, a Drosophila homologue of mammalian TBX1, in these cells.     

Influence of parental chromosomes on spatial specificity in androgenetic----parthenogenetic chimaeras in the mouse

The presence of both parental genomes is essential for development to term in the mouse embryo probably because of germline-specific modifications of homologous chromosomes. Neither androgenetic nor parthenogenetic embryos can by themselves develop to term; any post-implantation embryos they produce have opposite phenotypes, which reflects the presence of complementary information in parental chromosomes. The development of androgenetic----parthenogenetic chimaeras is of considerable interest because in this case both parental chromosomes are available even though they are in separate cells. We demonstrate here that in post-implantation chimaeric fetuses, the expression of parental information results in spatial specificity so that parthenogenetic cells are confined to the embryo but the trophoblast consists almost entirely of androgenetic cells. The yolk sac contains both cell types. However, there is incomplete functional complementation because the chimaeras do not reach term. Although failure to reach term may occur partly because of inadequate intermingling and interactions between embryonic cells, it is more likely that further control of mouse development depends on the presence of both sets of chromosomes within the same cells.     

Antennal proteins involved in the neural mechanism of quinone inhibition of insect feeding

Zusammenfassung Es wird gezeigt, dass der radioaktiv markierte Frasshemmstoff Methylnaphthochinon in den Antennen vonPeriplanetu an 2 spezifische, mit Triton X-100 extrahierbare, elektrophoretisch trennbare Proteine gekoppelt wird.