Algunos aspectos generales de la producción y comercialización del sorgo en el Magdalena

Después de varios meses de investigación, mediante encuestas, entrevistas y observaciones en los canales que intervienen directa o Indirectamente en la producción y comercialización del producto, (productores de sorgo, comerciantes de él, productores de concentrado y comerciantes en todos los niveles), se ha logrado elaborar el presente estudio, que se espera sea de alguna utilidad. Él se realizó con muchas dificultades, entre las cuales se destacan; a) La negativa de los sorteros para suministrar información; b) La carencia de estadísticas; c) La falta de registros de costos que permitan elaborar aproximadamente los estudios; y d) Otro sin número de problemas menores. El. Estudio contempla Las siguientes partes; En la primera sé estudian aspectos sobre la historia y generalización de Los sorgos, crecimiento y situación actual de la producción del sorgo y aspecto económico y social. En la segunda parte se analizan Las zonas ecológicas recomendables para sorgo en la Costa Atlántica o Lo que es igual Localización geográfica de las regiones productoras. Él se realizó con muchas dificultades, entre las cuates se destacan; a) La negativa de los sorgeros para suministrar información; b) La carencia de estadísticas; c) La falta de registros de costos que permitan elaborar aproximadamente los estudios; y d) Otro sin número de problemas menores. El. estudio contempla Las siguientes partes; En la primera sé estudian aspectos sobre la historia y generalización de Los sorgos, crecimiento y situación actual de la producción del sorgo y aspecto económico y social. En la segunda parte se analizan Las zonas ecológicas recomendables para sorgo en la Costa Atlántica o Lo que es igual Localización geográfica de las regiones productoras

Ligand-dependent spatiotemporal signaling profiles of the mu-opioid receptor are controlled by distinct protein-interaction networks

Ligand-dependent differences in the regulation and internalization of the mu-opioid receptor (MOR) have been linked to the severity of adverse effects that limit opiate use in pain management. MOR activation by morphine or [D-Ala2,N-MePhe4,Gly-ol]-enkephalin (DAMGO) causes differences in spatiotemporal signaling dependent on MOR distribution at the plasma membrane. Morphine stimulation of MOR activates a Gai/o–Gbg–protein kinase C (PKC)a phosphorylation pathway that limits MOR distribution and is associated with a sustained increase in cytosolic extracellular signal–regulated kinase (ERK) activity. In contrast, DAMGO causes a redistribution of the MOR at the plasma membrane (before receptor internalization), that facilitates transient activation of cytosolic and nuclear ERK. Here, we used proximity biotinylation proteomics to dissect the different protein-interaction networks that underlie the spatiotemporal signaling of morphine and DAMGO. We found that DAMGO, but not morphine, activates Ras‐related C3 botulinum toxin substrate 1 (Rac1). Both Rac1 and nuclear ERK activity was dependent on the scaffolding proteins IQ motif–containing GTPase-activating protein-1 (IQGAP1) and Crk-like protein (CRKL). In contrast, morphine increased the proximity of the MOR to desmosomal proteins, which form specialized and highly ordered membrane domains. Knockdown of two desmosomal proteins, junction plakoglobin (JUP) or desmocolin-1 (DSC1), switched the morphine spatiotemporal signaling profile to mimic that of DAMGO, resulting in a transient increase in nuclear ERK activity. The identification of the MOR-interaction networks that control differential spatiotemporal signaling reported here is an important step towards understanding how signal compartmentalization contributes to opioid-induced responses including anti-nociception and the development of tolerance and dependence

Identities of P2 and P3 Residues of H-2K^b-Bound Peptides Determine Mouse Ly49C Recognition

<div><p>Ly49 receptors can be peptide selective in their recognition of MHC-I-peptide complexes, affording them a level of discrimination beyond detecting the presence or absence of specific MHC-I allele products. Despite this ability, little is understood regarding the properties that enable some peptides, when bound to MHC-I molecules, to support Ly49 recognition, but not others. Using RMA-S target cells expressing MHC-I molecules loaded with individual peptides and effector cells expressing the ectodomain of the inhibitory Ly49C receptor, we found that two adjacent amino acid residues, P2 and P3, both buried in the peptide binding groove of H-2K^b, determine mouse Ly49C specificity. If both are aliphatic residues, this is supportive. Whereas, small amino acids at P2 and aromatic amino acids at the P3 auxiliary anchor residue are detrimental to Ly49C recognition. These results resemble those with a rat Ly49 where the identity of a peptide anchor residue determines recognition, suggesting that dependence on specific peptide residues buried in the MHC-I peptide-binding groove may be fundamental to Ly49 peptide selectivity and recognition.</p></div

Peptide residues P2 and P3 determine Ly49C recognition of H-2K^b.

<p><b>(A)</b> Expression of H-2K^b incubated with the indicated peptides. <b>(B)</b> Percent cytotoxicity of RMA-S targets incubated with the indicated peptides incubated with RNK.49W/C effectors. <b>(C)</b> Statistically significant changes in Ly49W/C recognition of H-2K^b, with respect to the positive control for RNK.49W/C recognition (SIINFEKL-loaded RMA/S cells), were conducted at the 12.5:1 E:T ratio from cytotoxicity assays (**<i>p</i> < 0.005). Results plotted are the mean of three independent experiments with error bars representing SD.</p

Sequence and origin of H-2K^b specific peptides bearing non-polar aliphatic auxiliary anchor residues.

<p>Bold indicates primary anchor residue, bold and underlined indicates P3 auxiliary anchor residue.</p><p>Sequence and origin of H-2K^b specific peptides bearing non-polar aliphatic auxiliary anchor residues.</p

Structural analysis of peptide amino acid docking into the D-pocket of H-2K^b.

<p>The auxiliary anchor residue at position 3 (P3) docks into the shallow D-pocket of H-2K^b formed by residues within the α2-helix. Comparison of P3 in H-2K^b-SIINFEKL and H-2K^b-RGYVYQGL, complexes that do or do not support Ly49C-H-2K^b interaction, respectively. The figure shows the H-2K^b-SIINFEKL heavy chain in pink ribbon, the SIINFEKL peptide is in dark red; the H-2K^b-RGYVYQGL heavy chain is in gray ribbon, the RGYVYQGL peptide is in teal. The figure was generated using CHIMERA UCSF software and PDB IDs IVAC for H-2K^b-SIINFEKL and 1KPU for H-2K^b-RGYVYQGL.</p

Ly49C peptide dependent recognition of H-2K^b decreases with peptides bearing non-polar aliphatic auxiliary anchor residues.

<p><b>(A)</b> RMA-S cell surface expression of H-2K^b when incubated with the indicated peptides, or no peptide. Shaded histogram corresponds to isotype control. <b>(B)</b> Cytotoxicity assay using RMA-S cells loaded with peptides that have aromatic R groups at P3 co-incubated with RNK.49WC effector cells. <b>(C)</b> Statistically significant changes in Ly49W/C recognition of H-2K^b, with respect to the positive control for RNK.49W/C recognition (SIINFEKL-loaded RMA/S cells), were performed at the 12.5:1 E:T ratio from cytotoxicity assays (*<i>p</i> < 0.05, **<i>p</i> < 0.005). Results plotted are the mean of three independent experiments with error bars representing SD.</p

Predicted peptide binding affinity to H-2K^b for peptides supportive of Ly49W/C and H-2K^b interaction.

<p>The predicted IC₅₀ values for H-2K^band specific peptides that support Ly49W/C recognition of H-2K^b were obtained using the server NetMHCpan. Predictions were set up to have IC₅₀ value of 10nM for strong affinity and IC₅₀ value of 500nM for weak affinity. In the peptide sequence bold indicates primary anchor residue, bold and underlined indicates P3 auxiliary anchor residue.</p><p>Predicted peptide binding affinity to H-2K^b for peptides supportive of Ly49W/C and H-2K^b interaction.</p

Sequence and origin of H-2K^b specific peptides bearing aromatic auxiliary anchor residues.

<p>Bold indicates primary anchor residue, bold and underlined indicates P3 auxiliary anchor residue.</p><p>Sequence and origin of H-2K^b specific peptides bearing aromatic auxiliary anchor residues.</p

Structural analysis of peptide amino acid docking into the B-pocket of H-2K^b.

<p>The H-2K^b bound peptide amino acid at position 2 (P2) docks into the B-pocket of H-2K^b in H-2K^b-RGYVYQGL. Figure shows the H-2K^b-RGYVYQGL heavy chain in gray ribbon, the RGYVYQGL peptide is in teal. The figure was generated using CHIMERA UCSF software and PDB ID 1KPU for H-2K^b-RGYVYQGL.</p