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Os resultados do ensaio de seleções regionais de progênies de café, plantado em Jaú, em 1951, são apresentados e confrontados com os dados de um ensaio semelhante, plantado em Campinas, nessa mesma época. Os 64 itens do ensaio de Jaú compreendem progênies dos cultivares 'Mundo Nôvo', 'Bourbon Amarelo', 'Bourbon Vermelho', 'Caturra Amarelo' e 'Caturra Vermelho', além de testemunhas desses cultivares, sem seleção, e do 'Típica', testemunha geral do ensaio. Os resultados obtidos mostram que as progênies de café 'Mundo Nôvo' são as mais vigorosas e produtivas; apresentam sementes de maior diâmetro e mais pesadas e maior ocorrência de grãos chatos, do tipo normal. Produzem, em média, 35 por-cento a mais do que as progênies selecionadas do 'Bourbon Amarelo', 84, 178 e 232 por-cento a mais do que as do 'Bourbon Vermelho', 'Caturra' e 'Típica', respectivamente. Além disto, produziram 77 por-cento a mais do que o 'Mundo Nôvo' sem seleção. Dentre as progênies do 'Mundo Nôvo', destacou-se a de prefixo MP 376-4, em tôdas as características analisadas. As progênies selecionadas do 'Bourbon Amarelo' deram 38 por-cento a mais do que as de 'Bourbon Vermelho' e de 146 por-cento a mais do que o 'Típica'. O exame do comportamento das melhores progênies dos cultivares 'Mundo Nôvo', 'Bourbon Amarelo' e 'Bourbon Vermelho', em confronto com os dados obtidos em Campinas, indicam que as do 'Mundo Nôvo' e 'Bourbon Vermelho' têm maior capacidade de adaptação, no sentido de que se comportam igualmente bem nessas duas localidades. Os dados obtidos cnníirmam os diferentes níveis de produção do 'Mundo Nôvo', 'Bourbon Amarelo' e 'Bourbon Vermelho', já observados em outros ensaios de café e indicam que as progênies do 'Mundo Nôvo' MP 376-4, CP 379-19, JP 381-3 e CP 387-17 se adaptam bem às condições locais, devendo, por êsse motivo, ser preferidas para plantio em larga escala.

Integral membrane proteins represent a large and essential portion of the proteome that often prove challenging for structural studies. We demonstrate a synergistic approach to structurally model topologically complex integral membrane proteins by combining coevolutionary constraints and computational modeling with biochemical validation. We report the first structural model of a eukaryotic membrane-bound O-acyltransferase (MBOAT), ghrelin O-acyltransferase (GOAT), which modifies the metabolism-regulating hormone ghrelin. Our structure suggests an unanticipated strategy for trans-membrane protein acylation, with catalysis occurring in an internal channel as GOAT acts as an "enzyme inside a pore". Our structure opens the door to structure-guided inhibitor design targeting GOAT and other MBOAT family members while validating the power of our approach to generate predictive structural models for other experimentally challenging integral membrane proteins.

Ghrelin O-acyltransferase (GOAT) plays a central role in the maturation and activation of the peptide hormone ghrelin, which performs a wide range of endocrinological signaling roles. Using a tight-binding fluorescent ghrelin-derived peptide designed for high selectivity for GOAT over the ghrelin receptor GHSR, we demonstrate that GOAT interacts with extracellular ghrelin and facilitates ligand cell internalization in both transfected cells and prostate cancer cells endogenously expressing GOAT. Coupled with enzyme mutagenesis, ligand uptake studies support the interaction of the putative histidine general base within GOAT with the ghrelin peptide acylation site. Our work provides a new understanding of GOAT's catalytic mechanism, establishes that GOAT can interact with ghrelin and other peptides located outside the cell, and raises the possibility that other peptide hormones may exhibit similar complexity in their intercellular and organismal-level signaling pathways.

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Ghrelin O-acyltransferase (GOAT) plays a central role in the maturation and activation of the peptide hormone ghrelin, which performs a wide range of endocrinological signaling roles. Using a tight-binding fluorescent ghrelin-derived peptide designed for high selectivity for GOAT over the ghrelin receptor GHS-R1a, we demonstrate that GOAT interacts with extracellular ghrelin and facilitates ligand cell internalization in both transfected cells and prostate cancer cells endogenously expressing GOAT. Coupled with enzyme mutagenesis, ligand uptake studies provide the first direct evidence supporting interaction of the putative histidine general base within GOAT with the ghrelin peptide acylation site. Our work provides a new understanding of GOAT's catalytic mechanism, establishes a key step required for autocrine/paracrine ghrelin signaling involving local reacylation by GOAT, and raises the possibility that other peptide hormones may exhibit similar complexity in their intercellular and organismal-level signaling pathways.

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