Synthesis and secretion of serum gelsolin by smooth muscle tissue

Gelsolin is one of many actin binding proteins which regulate the structure of intracellular microfilaments. A secretory form of gelsolin, a protein also known as "actin depolymerizing factor" or "brevin," is present in animal sera. In the present studies, we: demonstrate that a 90-kDa secretory protein produced by chicken gizzard smooth muscle is serum gelsolin; show that chicken serum gelsolin, as compared with its mammalian counterparts, lacks 26 amino acid residues at its NH2-terminal end; show that gizzard smooth muscle devotes on the order of 100 times more of its total protein synthetic effort (about 1% of the total) to the production of serum gelsolin than does liver, a previously speculated major source of this protein; and give evidence that rat tissues which are rich in smooth muscle cells (blood vessels, uterine muscle) also produce serum gelsolin. Our work suggests that, in vivo, smooth muscle-containing tissues may be major producers of the serum form of this actin binding protein.     

Production of fumonisins by Fusarium moniliforme strains from various substrates and geographic areas.

Strains of Fusarium moniliforme from different geographic areas and from corn and other substrates were tested for the ability to produce fumonisins in culture. The test results indicate that the potential exists for production of fumonisins by such strains in agricultural commodities and other substrates in widespread geographic areas.     

Synthesis of apolipoprotein A1 in skeletal muscles of normal and dystrophic chickens

We recently observed that, around the time of hatching, chick skeletal muscles synthesize and secrete apolipoprotein A1 (apo-A1) at high rates and that reinitiation of synthesis of this serum protein to high levels occurs in mature chicken breast muscle following surgical denervation (Shackelford, J. E., and Lebherz, H. G. (1983) J. Biol. Chem. 258, 7175-7180; 14829-14833). In the present work we investigate the effect of avian muscular dystrophy on the synthesis of apo-A1 in chicken muscles. The relative rate of synthesis of apo-A1 and levels of apo-A1 RNA in mature dystrophic breast (fast-twitch) muscle were about 6-fold higher than normal, while synthesis of apo-A1 in breast muscles derived from 2-day-old dystrophic chicks was close to normal. These observations suggest that the elevated apo-A1 synthetic rate in mature dystrophic breast muscle results from a failure of the diseased tissue to "shut down" apo-A1 synthesis to the normal level during postembryonic maturation. Apo-A1 synthesis in the "slow-twitch" lateral adductor muscle of dystrophic chickens was found to be normal. Our work is discussed in terms of the apparent similarities between the effects of surgical denervation and muscular dystrophy on the protein synthetic programs expressed by chicken skeletal muscles.     

Regulation of apolipoprotein A1 synthesis in avian muscles

Until recently, liver and intestinal mucosa were believed to be the sole sites of synthesis of apolipoprotein A1 (Apo-A1), the major protein component of serum high density lipoprotein particles. We recently showed (Shackelford, J.E., and Lebherz, H.G. (1983) J. Biol. Chem. 258, 7175-7180) that chick breast muscle also synthesizes and secretes Apo-A1 but does so at high rates only around the time of hatching. In the present work, we investigate the regulation of synthesis of Apo-A1 in chicken muscles. 1) The primary translation product encoded for by muscle Apo-A1 mRNA is about 2600 daltons larger than the mature serum protein which is consistent with the idea that, like its mammalian liver counterpart, chick muscle Apo-A1 mRNA codes for an NH2-terminal extension (prepro segment) which is 24 amino acids long. 2) The developmentally regulated rise and fall in muscle Apo-A1 synthesis which occurs around the time of hatching is associated with a large accumulation followed by depletion of Apo-A1 mRNA molecules during this period. 3) Reinitiation of Apo-A1 synthesis to high levels in mature breast muscle occurred in vivo following surgical denervation and in vitro by maintaining breast muscle explants for several days in defined culture media. 4) Cardiac, but not smooth, muscles also synthesize and secrete Apo-A1 at high levels around the time of hatching. These and other observations are discussed in terms of possible regulatory "signals" which may control Apo-A1 synthesis in avian muscles.     

Restricted Ig H chain V gene usage in the human antibody response to Haemophilus influenzae type b capsular polysaccharide

The mechanisms that govern the content of the human antibody repertoire are poorly understood. To investigate the antibody response to a clinically relevant Ag, we have produced heterohybridomas secreting human antibodies directed against the capsular polysaccharide of Haemophilus influenzae type b (Hib PS). Immune lymphocytes were harvested 7 days after immunization with either of two vaccine formulations, a plain polysaccharide vaccine (Hib PS) or a polysaccharide-protein conjugate of Hib PS and diphtheria toxoid (Hib PS-D). H chain V region gene nucleic acid sequences were determined for five stable hybridomas. All use members of the VHIII gene family and are 83% to 98% homologous to two candidate germ-line sequences. A variety of D and JH segments are used. Thus the Ig H chain repertoire appears to be restricted to a limited group of VHIII family members. The previously reported expression of homologous sequences in the human fetal repertoire suggests that the inability of young children to respond to this Ag is not caused by deficiencies of these important elements early in development. The restricted use of VHIII gene segments suggests that this gene family plays a pivotal role in the immune response to this important childhood pathogen.     

Ligand-stimulated tyrosine phosphorylation of the IL-2 receptor beta chain and receptor-associated proteins.

Interleukin-2 (IL-2) stimulates the rapid phosphorylation on tyrosine of several specific cellular proteins. However, the high-affinity human IL-2 receptor, composed of an alpha (p55) and beta (p70/75) subunit, does not contain a cytoplasmic tyrosine kinase domain. In this study, we investigated the identities of the proteins phosphorylated on tyrosine in response to IL-2 stimulation to examine possible pathways of signal transduction. By the use of immunoblotting with anti-phosphotyrosine antibodies, we demonstrate that IL-2 augments tyrosine phosphorylation of the IL-2 receptor beta chain in human cell lines expressing either high-affinity (alpha/beta) receptors or only the beta chain. In IL-2-dependent mouse T cell lines, a 100,000-Da protein was phosphorylated on tyrosine in response to IL-2 and is proposed to be the mouse IL-2 receptor beta chain. Two other cellular proteins, pp55 and pp105 in human or pp55 and pp115 in mouse cell lines, were phosphorylated on tyrosine in response to IL-2 and coimmunoprecipitated with the high-affinity IL-2 receptor after chemical crosslinking of IL-2-stimulated cells. Thus, the IL-2 receptor may associate with additional subunits or with cellular proteins involved in signal transduction.     

Plasminogen activator and collagenase production by cultured capillary endothelial cells

Cultured bovine capillary endothelial (BCE) cells produce low levels of collagenolytic activity and significant amounts of the serine protease plasminogen activator (PA). When grown in the presence of nanomolar quantities of the tumor promoter 12-O-tetradecanoyl phorbol-13-acetate (TPA), BCE cells produced 5-15 times more collagenolytic activity and 2-10 times more PA than untreated cells. The enhanced production of these enzymes was dependent on the dose of TPA used, with maximal response at 10(-7) to 10(-8) M. Phorbol didecanoate (PDD), an analog of TPA which is an active tumor promoter, also increased protease production. 4-O-methyl-TPA and 4α-PDD, two analogs of TPA which are inactive as tumor promoters, had no effect on protease production. Increased PA and collagenase activities were detected within 7.5 and 19 h, respectively, after the addition of TPA. The TPA-stimulated BCE cells synthesized a urokinase-type PA and a typical vertebrate collagenase. BCE cells were compared with bovine aortic endothelial (BAE) cells and bovine embryonic skin (BES) fibroblasts with respect to their production of protease in response to TPA. Under normal growth conditions, low levels of collagenolyic activity were detected in the culture fluids from BCE, BAE, and BES cells. BCE cells produced 5-13 times the basal levels of collagenolytic activity in response to TPA, whereas BAE cells and BES fibroblasts showed a minimal response to TPA. Both BCE and BAE cells exhibited relatively high basal levels of PA, the production of which was stimulated approximately threefold by the addition of TPA. The observation that BCE cells and not BAE cells produced high levels of both PA and collagenase activities in response to TPA demonstrates a significant difference between these two types of endothelial cells and suggests that the enhanced detectable activities are a property unique to bovine capillary and microvessel and endothelial cells.     

The power of data synthesis to shape the future of the restoration community and capacity

Restoration efforts will be taking place over the next decade(s) in the largest scope and capacity ever seen. Immense commitments, goals, and budgets are set, with impactful wide‐reaching potential benefits for people and the environment. These are ambitious aims for a relatively new branch of science and practice. It is time for restoration action to scale up, the legacy of which could impact over 350 million hectares targeted for the U.N. Decade on Ecosystem Restoration. However, restoration still proceeds on a case‐by‐case, trial by error basis and restoration outcomes can be variable even under similar conditions. The ability to put each case into context—what about it worked, what did not, and why—is something that the synthesis of data across studies can facilitate. The link between data synthesis and predictive capacity is strong. There are examples of extremely ambitious and successful efforts to compile data in structured, standardized databases which have led to valuable insights across regional and global scales in other branches of science. There is opportunity and challenge in compiling, standardizing, and synthesizing restoration monitoring data to inform the future of restoration practice and science. Through global collation of restoration data, knowledge gaps can be addressed and data synthesized to advance toward a more predictive science to inform more consistent success. The interdisciplinary potential of restoration ecology sits just over the horizon of this decade. Through truly collaborative synthesis across foci within the restoration community, we have the opportunity to rapidly reach that potential and achieve extraordinary outcomes together.     

Evolution and functions of human dance

Dance is ubiquitous among humans and has received attention from several disciplines. Ethnographic documentation suggests that dance has a signaling function in social interaction. It can influence mate preferences and facilitate social bonds. Research has provided insights into the proximate mechanisms of dance, individually or when dancing with partners or in groups. Here, we review dance research from an evolutionary perspective. We propose that human dance evolved from ordinary (non-communicative) movements to communicate socially relevant information accurately. The need for accurate social signaling may have accompanied increases in group size and population density. Because of its complexity in production and display, dance may have evolved as a vehicle for expressing social and cultural information. Mating-related qualities and motives may have been the predominant information derived from individual dance movements, whereas group dance offers the opportunity for the exchange of socially relevant content, for coordinating actions among group members, for signaling coalitional strength, and for stabilizing group structures. We conclude that, despite the cultural diversity in dance movements and contexts, the primary communicative functions of dance may be the same across societies.     

Markers on Bovine Chromosome 20 Associated with Carcass Quality and Composition Traits and Incidence of Contracting Infectious Bovine Keratoconjunctivitis

The objective of this study was to use single nucleotide polymorphisms (SNP) located on bovine chromosome 20 to fine map a previously identified QTL associated with the incidence of infectious bovine keratoconjunctivitis (IBK). Crossbred steers (GPE 7; n = 539) derived from sires of 7 Bos taurus breeds and having veterinary records related to IBK were used to test the association of a total of 105 SNP located under the most relevant region of the QTL. Five SNP were significantly associated with IBK (P < 0.05), as animals inheriting differing genotypes from individual SNP exhibited significantly different incidence rates of IBK. The population also had numerous other phenotypes, supporting evaluation of association of the 105 markers with carcass traits to identify potential antagonistic effects of implementing a marker-assisted selection program for IBK susceptibility. An association of 2 SNP for marbling and tenderness was identified, along with 3 SNP associated with the percentage of carcasses classified as choice. Four SNP were significantly associated with fat yield, 2 SNP with longissimus muscle area, and 2 additional SNP with dressing percentage. The association of these markers indicates that the evaluated QTL region may, in fact, harbor the causative mutations responsible for the variation observed in IBK susceptibility and carcass quality and composition traits. Thus, further evaluation of SNP in this region is necessary in order to identify mutations accounting for the largest degree of variation for IBK and carcass traits.