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Haining Yu

Publications and source records attributed to Haining Yu.

7 recordsLinked to original sources
PubMed2007

Multiple bombesin-like peptides with opposite functions from skin of Odorrana grahami.

Bombesin-like peptides (BLPs) are a family of neuroendocrinic peptides that mediate a variety of biological activities. Three mature BLPs from the skin secretions of the frog Odorrana grahami were purified. Several bombesin-like peptide cDNA sequences encoding precursors of BLPs were identified from the skin cDNA library of O. grahami. This is the maximal diversity of BLPs ever found in animals. Five mature BLPs (B1-B5) based on the amino acid sequences derived from the cDNA cloning were synthesized. In the in vitro myotropic contraction experiment, all synthesized BLPs displayed a stimulating effect toward rat stomach strips, except B4 and B5 which showed the opposite effect, suggesting that certain BLPs may act as antagonists of bombesin receptors while most other BLPs act as agonists. This finding will facilitate the finding of novel bombesin receptors and novel ligands of bombesin receptors. The diversity of amphibian BLPs and their precursors were also analyzed and results suggest that amphibian BLPs and corresponding precursors of various sizes and processing patterns can be used as markers of taxonomic and molecular phylogenetics. The remarkable similarity of preproregions gives rise to very different BLPs and 3'-terminal regions in distantly related frog species, suggesting that the corresponding genes form a multigene family originating from a common ancestor. The diversification of BLP loci could thus be part of an evolutionary strategy developed by amphibian species as a result of shifts to novel ecological niches when environmental factors change rapidly.

Amino Acid Sequence↗
PubMed2006

The mastoparanogen from wasp.

Mastoparans are a family of small peptides identified from the venom of hymenopteroid insects. Although they have been characterized as early as 1979, and so far are recognized as a leading biomolecule in potential drug therapy, their precursors, mastoparanogen, have still not been determined. In this paper, several mastoparans from the venom of the wasp Vespa magnifica (Smith) are reported. The cDNA of mastoparanogen is 236 base pairs in length, and encodes 40 amino acid residues, including a N-terminal acidic fragment and a C-terminal mature basic mastoparan, which contain multiple acidic amino acid residues and a tetradecapeptide with three lysines, INLKAIAALAKKLLG, respectively. The glycine at the tetradecapeptide end is the donator of -NH(4) for the amidation of the leucine at the C-terminal. As far as we know, this is the first report of the precursor of animal mastoparan.

Amino Acid Sequence↗
PubMed2006

Two families of antimicrobial peptides with multiple functions from skin of rufous-spotted torrent frog, Amolops loloensis.

There are around 27 species of Amolops amphibian distributed in South-east of Asia. Seven antimicrobial peptides (AMPs) belonging to two different families were purified from skin of rufous-spotted torrent frog, Amolops loloensis, and designated brevinins-ALa, b, c, and d, and temporins-ALa, b, and c. The brevinins-AL family which is structurally related to brevinins-1 from skin secretions of the European frog, Rana brevipoda, is composed of 24 amino acids and has an intra-disulfide bridge at the C-terminus. The temporins-AL family, composed of 13 or 16 amino acid residues, is related with temporins from the skin secretions of R. temporaria. The findings of this study will facilitate the solutions to the taxonomic questions of the ranid genus Amolops and Staurois. In the work of this paper, both brevinins-ALb and temporin-Ma induced mast cell degranulation and histamine release, and had cytotoxic activity toward solid tumor cell line HepG(2). Brevinins-ALb also exerted strong hemolytic activity while temporin-Ma had no such activity.

Amino Acid Sequence↗
PubMed2006

A tick B-cell inhibitory protein from salivary glands of the hard tick, Hyalomma asiaticum asiaticum.

Some studies done to date suggest that B-cell inhibitory factor occurred in tick saliva. In this study, a novel protein having B-cell inhibitory activity was purified and characterized from the salivary glands of the hard tick, Hyalomma asiaticum asiaticum. This protein was named B-cell inhibitory factor (BIF). The cDNA encoding BIF was cloned by cDNA library screening. The predicted protein from the cDNA sequence is composed of 138 amino acids including the mature BIF. No similarity was found by Blast search. The lipopolysaccharide-induced B-cell proliferation was inhibited by BIF. This is the first report of the identification and characterization of B-cell inhibitory protein from tick. The current study facilitates the study of identifying the interaction among tick, Borrelia burgdorferi, the causative agent of Lyme disease, and host.

Amino Acid Sequence↗
PubMed2005

Direct antimicrobial activities of PR-bombesin.

PR-bombesin is a bombesin-like peptide derived from the skin of the Chinese red belly toad, Bombina maxima. The 8-residue segment of N-terminal of RP-bombesin, comprising four prolines and three basic residues, is extensively different from other bombesin-like peptides. Since sequence of Pro-Arg-Pro generally plays an important role in the antimicrobial activity of proline-rich antimicrobial peptides, the componential feature of PR-bombesin indicates that it may have antimicrobial activity. In this paper, we presented the first evidence that bombesin-like peptides possess direct antimicrobial activities as some neuropeptides. It was determined by CD spectroscopy that PR-bombesin adopted a combination of random coil and beta-sheet structure, suggesting RP-bombesin is a new member of antimicrobial peptides having beta structure but without disulfide bonds. Current results also supported that PR-bombesin plays a direct defensive role besides its neuro-endocrological functions.

Animals↗
PubMed2005

Kinetic studies on the interactions of heparin and complement proteins using surface plasmon resonance.

Heparin is a naturally occurring polysaccharide known to interact with complement proteins and regulate multiple steps in the complement cascade. Quantitative information, in the form of affinity constants for heparin-complement interactions, is not generally available and there are no reports of a comprehensive analysis using the same interaction method. Such information should improve our understanding of how exogenously administered pharmaceutical heparin and the related endogenous polysaccharide, heparan sulfate, regulate complement activation. The current study provides the first comprehensively analysis of the binding of various complement proteins to heparin using surface plasmon resonance (SPR). Complement proteins C1, C2, C3, C4, C5, C6, C7, C8, C9, C1INH, factor I, factor H, factor B and factor P all bind heparin but exhibit different binding kinetics and dissociation constants (Kd) ranging from 2 to 320 nM. By taking into account these Kd values and the serum concentrations of these complement proteins, the percentage of each binding to exogenously administered heparin was calculated and found to range from 2% to 41%. This study provides essential information required for the rational design of new therapeutic agents capable of regulating the complement activation.

Complement Activation↗