Equity issues in gender-affirming medical care in Kerala: a reflective commentary.

Gender-affirming medical care is the provision of transition-related medical services that support a transgender person's own gender identity. Gender transitioning is a process that requires not only social support but also psychological and medical support, This paper attempts to document the challenges faced by transgender individuals (TG) especially in the context of gender affirming medical care in the Kerala context. The transition process is extremely complex as the preference for such process is varied. Some transgender individuals preferred social transition and/or medical transition to align their gender expression with their gender identity, while others chose to have a gender expression or identity outside the traditional gender binary. In Kerala, despite proactive policy and positive legal support, transgender individuals face many challenges in gender-affirming medical care which include lack of family support and equity-related issues with respect to a number of social support institutions including health services. A few possible interventions are suggested such as changes in medical curriculum, more active State support and sensitization of the society including health workers.

Polymorphism in a serine protease inhibitor gene and its association with the resistance of bay scallop (Argopecten irradians) to Listonella anguillarum challenge.

Serine protease inhibitors (SPIs) play a crucial role in regulation of both host and bacterial serine protease. They are classified into several protein families, where Kazal-type inhibitors are one of families with multi-domain. In the present study, the polymorphism of AiSPI from Bay scallop Argopecten irradians was found to be associated with disease resistance of bay scallop against Listonella anguillarum. Nine single nucleotide polymorphisms (SNPs) were identified in the exon region of AiSPI, where five SNPs were non-synonymous mutation. Three of these mutations were located in "kazal-like 3"domain, two SNP loci positioned at +536, +1312 were selected for further association studies. For the locus +536, the genotype frequency of A/G in the resistant stock (12.8%) was significantly lower (p < 0.05) than that in the susceptible stock (35.1%), while, the genotype A/A in the resistant stock (87.2%) was significantly higher in comparison with susceptible stock (64.9%) (p < 0.05). The G allele frequencies were 6.4% and 17.6% in resistant stock and susceptible stock, respectively, and χ2-test revealed a significant difference in the frequency distribution between the two stocks (p < 0.05). But there was no significant association between the mutation C-T at locus +1312 with either resistant or susceptible group (p > 0.05). The genotype frequencies of T/T, T/C, C/C at locus +1312 were 94.6%, 2.7% and 2.7% respectively in the susceptible stock, while 100%, 0% and 0% respectively in the resistant stock. The amino acid change for the mutation at locus +536 A-G was from asparagine to serine, and the predicted homology model of this amino acid variation could affect its function as well as the structural integrity of the domain. In vitro elastase inhibition assay of the protein variants at locus +536 was conducted to explicate the effect of SNP. The increasing concentration of protein (0 mmol/L- 2.93 mmol/L) was incubated with 80 nmol/L elastase where the residual enzyme activity values for rAiSPI (N) with A variant and rAiSPI (S) with G variant were started to reduce from 0.40 to 0.215 and 0.435 to 0.356, respectively. The elastase inhibition ability of rAiSPI (N) variant was significantly higher than that of rAiSPI (S) (p < 0.01). The results suggested that the mutation at locus +536A/A significantly associated with disease resistance of bay scallop would shed light for selective breeding program.

An evolutionarily ancient NO synthase (NOS) in shrimp.

Nitric oxide (NO) is a well known essential molecule that is involved in multiple functions such as neuron transduction, cardiac disease, immune responses, etc.; nitric oxide synthase (NOS) is a critical enzyme that catalyzes the synthesis of it. A very few crustacean NOS molecules were biochemically characterized so far. In the present study, we cloned and characterized a NOS cDNA from haemocytes of tiger shrimp (Penaeus monodon) (PmNOS). The full-length of PmNOS cDNA contained 3997 bp, including a 5'UTR of 249 bp, ORF of 3582 bp and a 3'UTR of 166 bp. The putative peptide was 1193 amino acid residues in length, with an estimated molecular weight of 134.7 kDa and pI 6.7. Structurally, PmNOS contained oxygenase and reductase domains at N-terminal and C-terminal, respectively, and connected with a calmodulin binding motif. The deduced amino acid sequence of PmNOS shared 98% identical to the Chinese shrimp (Fenneropenaeus chinensis) NOS. Phylogenetically, PmNOS clustered with invertebrate NOS, but not clustered with iNOS, eNOS or nNOS found in vertebrates. PmNOS mRNA was expressed in many tissues or organs including thoracic and ventral nerves, midgut, gill, eyestalk, haemocytes, subcuticular epithelium and heart, but not found in hepatopancreas, muscle and lymphoid organ. But there was no significant difference in PmNOS mRNA expression after stimulation with LPS either by different concentration or time course or against CpG-ODN 2006. The enzyme activities of rPmNOS or crude homogenates from different tissues were detected, and were shown its highest activity in thoracic and ventral nerves, moderate in midgut and haemocytes but the lowest activity were seen in muscle. The addition of NOS antibody against NADPH binding domain leads to less activity which suggested that NADPH was an essential cofactor for PmNOS catalytic activity. The calcium dependency of PmNOS was ascertained using calmodulin inhibitor, Trifluroperazine. To confirm the population of haemocyte which produce NOS, the florescence test was assayed, and it implicated that the production of NO was catalyzed by subset of granulocytic NOS. Since the MW range, inducible/noninducible transcript, calcium-dependent activity and tissue distribution, we suggest that PmNOS may recognize as an ancient NOS evolutionarily.

Right Versus Wrong: A Qualitative Appraisal With Respect to Pandemic Trajectories of Transgender Population in Kerala, India.

The transgender population generally faces rights violations and discrimination in their day-to-day lives, which was exacerbated during the recent pandemic. This necessitates close scrutiny from an ethics perspective. Following directives from a 2014 Supreme Court judgement, Kerala became the first Indian state to implement a comprehensive policy to enforce the constitutional rights of transgender people. Despite such positive actions, a basic social tendency not to respect gender diversity has led to discrimination and marginalization. This was very evident during the pandemic. In this empirical work, we have documented the lives of the transgender community during the pandemic wherein they share experiences related to livelihood, interaction with the healthcare system, and acceptance in society vis-à-vis the pandemic. Simply providing third-gender status will not help the gender-marginalized community to grow to their fullest potential and have a better lifestyle on par with others in mainstream society.

Association between the polymorphism of CfPGRP-S1 gene and disease susceptibility/resistance of zhikong scallop (Chlamys farreri) to Listonella anguillarum challenge.

Peptidoglycan recognition protein (PGRP) is a pattern recognition receptor, playing important roles in the innate immune response against invasive pathogens. The single nucleotide polymorphism (SNP) loci in scallop PGRP gene (CfPGRP) were screened from Chlamys farreri to investigate their association with disease resistance of scallop against Listonella anguillarum. Thirteen SNP sites were identified in PGRP domain of CfPGRP, and two of them at positions 4407 and 4408 which are located in the same codon resulted in a nonsynonymous substitution. The genotype frequency of CG/CG in the resistant stock was significantly lower than that in susceptible stock (0% vs 32.4%), while that of CG/TA in the resistant stock was significantly higher than that in susceptible stock (P < 0.01). The pathogen-associated molecular patterns (PAMP) binding activity of two recombinant proteins, rCfPGRP-S1 (R) with CG variant in 4407-4408 site, rCfPGRP-S1 (Y) with TA variant in 4407-4408 site, were elucidated by examining their P/N value at 405 nm with ELISA assay. The in vitro binding activities of the two rCfPGRP-S1 variants to both lipopolysaccharide (LPS) and peptidoglycan (PGN) varied (P < 0.05) in a dose-dependent manner, and rCfPRPP-S1(Y) exhibited significantly higher affinity to PGN and LPS than that of rCfPGRP-S1(R) (P < 0.05). The growth inhibition assay was conducted to find the antibacterial activities of the two variants. Both rCfPGRP-S1(R) and rCfPGRP-S1 (Y) displayed obvious activity to suppress the growth of Escherichia coli, but there was no significant difference in suppression activity of two variants (P > 0.05). The results suggested that the polymorphism at locus 4407-4408 of CfPGRP-S1 considerably affected its PAMP binding activity, and the SNP locus 4407-4408 CG/TA was associated with disease resistance of scallop against L. anguillarum infection, which could be used as a candidate marker for future selection in zhikong scallop breeding program.

Association of CfLGBP gene polymorphism with disease susceptibility/resistance of Zhikong scallop (Chlamys farreri) to Listonella anguillarum.

Lipopolysaccharide and ß-1, 3-glucan binding protein (LGBP) is a pattern recognition receptor (PRR) recognizing and binding both LPS and ß-1, 3-glucan, playing important roles in innate immunity. In the present study, the single nucleotide polymorphisms (SNPs) were assessed in LGBP gene from scallop Chlamys farreri (designated CfLGBP), and eight SNPs were found in its potential LPS and glucanase binding motif. The locus +7679 with the transition of G-A, which produced an amino acid substitution at codon 360 from a non polar Glycine to polar Serine, was selected to inspect their association with disease resistance/susceptibility to Listonella anguillarum. Three genotypes G/G, G/A and A/A, were revealed at locus +7679, and their frequencies were 89.7%, 7.7% and 2.6% in the resistant stock, while 63.2%, 34.2% and 2.6% in the susceptible stock, respectively. The frequency of genotypes G/G and G/A were significantly different (P < 0.05) between the two stocks. The pathogen-associated molecular patterns (PAMP) binding activity of two recombinant proteins, rCfLGBP (G) with G variant at locus +7679 and rCfLGBP (S) with A variant at locus +7679, were elucidated by ELISA assay. The binding affinities of both LPS and ß-glucan binding affinity were varied in a dose-dependent manner, where the binding affinity of rCfLGBP (G) was significantly higher than that of rCfLGBP (S) (P < 0.05). The results collectively suggested that the polymorphism of +7679 G/G in CfLGBP possibly enhances the binding activity of LPS and ß-glucan, and was associated to disease resistance of scallop against L. anguillarum, which could be a potential marker applied in future selection of scallop with enhanced resistance to L. anguillarum.

cDNA cloning and characterization of a new member of the tumor necrosis factor receptor family gene from scallop, Chlamys farreri.

Tumor necrosis factors receptor (TNFR) is a superfamily of proteins derived mainly from vertebrates. It plays significant role in diverse physiological and pathological events such as inflammation, apoptosis, autoimmunity and organogenesis. The gene of a new member of TNFR family, designated as CfTNFR2, was cloned and characterized from scallop, Chlamys farreri. The full-length cDNA of CfTNFR2 consisted of 1,501 nucleotides with a poly (A) tail, encoding a polypeptide of 378 amino acids with the estimated molecular mass of 42.70 kDa and predicted isoelectric point of 4.79. The characteristic motifs of the TNFR family proteins, such as three TNFR homology domains (also called CRD domains) and a death domain, were identified in CfTNFR2. Significantly, the deduced amino acid sequence of CfTNFR2 was closely homologous with mammalian osteoprotegerins showing approximately 37% identity. However, it shared only 11% amino acids identity with CfTNFR1, another TNFR homolog previously identified from the candidate scallop species, indicating that CfTNFR2 is a new molluscan TNFR protein. The spatial expression of CfTNFR2 in the tissues of the healthy and bacterial challenged scallops was detected by real-time PCR. CfTNFR2 mRNA was expressed constitutively in all selected tissues such as mantle, gill, gonad, hepatopancreas and hemocyte, among which gill and mantle displayed comparatively higher expression levels. Upon Listonella anguillarum challenge, CfTNFR2 expression was found to be remarkably up-regulated, especially in the tissues of gill (15.9-fold) and mantle (8.0-fold). The results reveal that CfTNFR2 is a constitutive and inducible acute-phase protein apparently involved in immune defense. The presence of CfTNFR2 (present study) and CfTNFR1 (previously identified from our lab) encouraged us to suggest that multiple members of TNFR family exist in mollusk, and the findings would help us to get better understanding on the evolutionary origin and functions of this protein family in mollusks.

Polychromatic luminescence and improved antifungal performance of succinic acid in the lattice of L-Lysine monohydrochloride.

The incorporation of succinic acid (SA) in the lattice of L-Lysine monohydrochloride (LM) has opened the new avenue in the field of production and application of scintillator materials such as LED and antifungal drug. Crystalline trait and monoclinic structure were scanned by XRD. The existence of carbonyl, carboxylate and protonated amine group were confirmed through FTIR and UV spectra predicted the transmittance of SA: LM crystal. Polychromatic luminescence behaviour had achieved through the incorporation of SA instead of blue luminescence, which is a new result. Also SA: LM exhibited good response towards pathogenic fungi which causes numerous types of infections and diseases in both humans and animals. The high inhibitory zone at 16 mm was formed by the grown SA: LM crystal against the life threatening fungi like Candida albicans. Also fungal inhibition against candida parapsilosis and Aspergillus flaves, respectively, were tuned by the inclusion of succinic acid.

Identification and characterization of a Cystatin gene from Chinese mitten crab Eriocheir sinensis.

Cystatins are a superfamily of proteins as reversible inhibitor of cysteine proteinases which play essential roles in a spectrum of physiological and immunological processes. In this study, a novel member of Cystatin superfamily was identified from Chinese mitten crab Eriocheir sinensis (designated EsCystatin) by expressed sequence tag (EST) analysis and rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of EsCystatin was of 1486 bp, consisting of a 5'-terminal untranslated region (UTR) of 92 bp, a 3' UTR of 1034 bp with a polyadenylation signal sequence AATAAA and a polyA tail, and an open reading frame (ORF) of 360 bp encoded a polypeptide of 120 amino acids with the theoretical isoelectric point of 5.48 and the predicted molecular weight of 13.39 kDa. A signal Cystatin-like domain (Gly(25) to Lys(112)) was found in the putative amino acid sequences of EsCystatin. Similar to other Cystatins, the conserved central Q(70)VVSG(74) motif was located in the Cystatin-like domain of EsCystatin. But EsCystatin lacked of signal peptide and disulphide bond. The EsCystatin exhibited homology with the other known Cystatins from invertebrates and higher vertebrates, and it was clustered into Cystatin family 1 in the phylogenetic tree. The mRNA transcripts of EsCystatin were mainly expressed in hemolymph, gill, hepatopancreas, gonad and muscle, and also marginally detectable in heart. After Listonella anguillarum challenge, the relative expression level of EsCystatin in hemolymph was down-regulated to 0.6-fold (P < 0.05) at 3 h post-challenge. Subsequently, it was up-regulated to 3.0-fold (P < 0.01) at 24 h. Afterwards, EsCystatin mRNA transcripts suddenly decreased to original level. After Pichia pastoris GS115 challenge, its mRNA expression level in hemolymph was up-regulated to the peak at 3 h (2.8-fold of that in blank (P < 0.01)). The cDNA fragment encoding the mature peptide of EsCystatin was recombined and expressed in Escherichia coli Rosetta-gami (DE3). The recombinant EsCystatin displayed a promoter inhibitory activity against papain. When the concentration of EsCystatin protein was of 300 microg mL(-1), almost 89% of papain activity could be inhibited. These results collectively suggested that EsCystatin was a novel member of protein in Cystatin family, was a potent inhibitor of papain and involved in immune response versus invading microorganisms.

Influence of most reactive inorganic cation in the optical and biological activities of L-Lysine monohydrochloride crystal.

Slow evaporation method was used to grow the pure and K+ ion doped L-Lysine monohydrochloride (L-LMHCL) crystals which has optical and antibiotic applications. The space group, structure and slight shifting of peaks are confirmed using single crystal XRD and the powder XRD. The FTIR analysis also shows that the K+ doped L-LMHCL has a slight shifting in the spectrum which indicates the functional group of L-LMHCL and the interaction between the K+ ions. The existence of K+ ion in the doped crystal is assured by the presence of potassium in the EDAX spectrum. The wide optical band gap was found for pure and K+ doped crystal using UV spectra and these are utilized in optoelectronic and nonlinear applications. The Kurtz Perry technique specified the NLO property of grown crystals. The dielectric property crystals was studied by varying the temperature. As a result, the highest dielectric constant is observed in doped crystal. An antibacterial activity against certain bacteria like E-coli, pseudomonas aeruginosa and staphylococcus aureus are provided by mm range for the grown crystals.

Studies on physicochemical and antibacterial deeds of amino acid based L-Threoninum sodium bromide.

Highly translucent nonlinear single crystals of L-Threoninum Sodium Bromide (LTSB) has been grown because of their rising need for everyday life and the XRD studies (PXRD and SXRD) solemnly affirmed the crystallinity and non-centrosymmetric space group of LTSB materials. The bonding nature and diverse functional groups in LTSB were demonstrated by FTIR analysis when they absorb infrared radiation. The optical behavior of LTSB crystals was explored through UV-Vis spectroscopy, which shows optical parameters depend on photon energy with band gap Eg = 5.7 eV which was suitable for optoelectronic devices. The electrical properties of LTSB crystals were measured by using dielectric measurement. The solid state parameters of LTSB crystal were calculated. An antibacterial activity developed by LTSB crystals against different pathogenic bacteria were examined using the Agar disk diffusion process. The antibacterial inhibitory activity of LTSB crystal revealed that it can be used to treat a variety of bacterial infections.

Correction: The New Face of the Old Molecules: Crustin Pm4 and Transglutaminase Type I Serving as RNPs Down-Regulate Astakine-Mediated Hematopoiesis.

[This corrects the article DOI: 10.1371/journal.pone.0072793.].

Transcriptome analysis of artificial hybrid pufferfish Jiyan-1 and its parental species: implications for pufferfish heterosis.

Jiyan-1 puffer, the F1 hybrid of Takifugu rubripes and Takifugu flavidus, displays obvious heterosis in the growth performance, flavor and stress tolerance. In the present study, comparative analysis for the transcriptomes of T. rubripes, T. flavidus and Jiyan-1 was performed aiming to reveal the possible mechanisms of heterosis in pufferfish. Whole transcriptomes were sequenced using the SOLiD4 platform, and a total of 44,305 transcripts corresponding to 18,164 genes were identified collectively. A total of 14,148 transcripts were differentially expressed. By comparing the gene expression patterns of the three samples, the coexistence of overdominance, dominance, underdominance and additivity was observed in the gene action modes of Jiyan-1. There were 2,237 transcripts in the intersection of the differentially expressed transcripts from Jiyan-1 versus T. rubripes and Jiyan-1 versus T. flavidus, among which 213 transcripts were also in the T. rubripes versus T. flavidus. The potential functions of the remaining 2,024 transcripts were mainly associated with metabolic process, nucleotide binding and catalytic activity. The enrichment results indicated metabolism was the most activated biological function in the heterosis. In addition, 35 KEGG pathways were retrieved as affiliated with more than three differentially expressed transcripts and 8,579 potentially novel transcript isoforms were identified for Jiyan-1. The present study revealed the coexistence of multiple gene actions in the hybrid puffer, indicated the importance of metabolism, ion binding function and kinase activity, as well as provided a list of candidate genes and pathways for heterosis. It could be helpful for the better understanding of the determination and regulation mechanisms of heterosis.

The new face of the old molecules: crustin Pm4 and transglutaminase type I serving as rnps down-regulate astakine-mediated hematopoiesis.

Astakine is an important cytokine that is involved in crustacean hematopoiesis. Interestingly, the protein levels of astakine increased dramatically in plasma of LPS-injected shrimp while mRNA levels remained unchanged. Here, we investigated the involvement of astakine 3'-untranslated region (UTR) in its protein expression. The 3'-UTR of astakine down-regulated the expression of reporter protein but the mRNA stability of reporter gene was unaffected. We identified the functional regulatory elements of astakine 3'-UTR, where 3'-UTR242-483 acted as repressor. The electrophoresis mobility shift assay (EMSA), RNA pull-down assay and LC/MS/MS were performed to identify the protein association. We noted that crustin Pm4 and shrimp transglutaminase I (STG I) were associated to astakine 3'-UTR242-483, while two other proteins have yet to be revealed. Depletion of hemocytic crustin Pm4 and STG I significantly increased the protein level of astakine while astakine mRNA level remained unaffected. Lipopolysaccharide (LPS) stimulated the secretion of crustin Pm4 and STG I from hemocytes to plasma and increased the astakine level to stimulate the hemocytes proliferation. Altogether, we identified the shrimp crustin Pm4 and STG I as novel RNA binding proteins that play an important role in down-regulating astakine expression at post-transcriptional level and are crucial for the maintenance of hematopoiesis.

A C1q domain containing protein from scallop Chlamys farreri serving as pattern recognition receptor with heat-aggregated IgG binding activity.

BACKGROUND: The C1q domain containing (C1qDC) proteins refer to a family of all proteins that contain the globular C1q (gC1q) domain, and participate in a series of immune responses depending on their gC1q domains to bind a variety of self and non-self binding ligands. METHODOLOGY: In the present study, the mRNA expression patterns, localization, and activities of a C1qDC protein from scallop Chlamys farreri (CfC1qDC) were investigated to understand its possible functions in innate immunity. The relative expression levels of CfC1qDC mRNA in hemocytes were all significantly up-regulated after four typical PAMPs (LPS, PGN, ß-glucan and polyI:C) stimulation. During the embryonic development of scallop, the mRNA transcripts of CfC1qDC were detected in all the stages, and the expression level was up-regulated from D-hinged larva and reached the highest at eye-spot larva. The endogenous CfC1qDC was dominantly located in the hepatopancreas, gill, kidney and gonad of adult scallop through immunofluorescence. The recombinant protein of CfC1qDC (rCfC1qDC) could not only bind various PAMPs, such as LPS, PGN, ß-glucan as well as polyI:C, but also enhance the phagocytic activity of scallop hemocytes towards Escherichia coli. Meanwhile, rCfC1qDC could interact with human heat-aggregated IgG, and this interaction could be inhibited by LPS. CONCLUSIONS: All these results indicated that CfC1qDC in C. farreri not only served as a PRR involved in the PAMPs recognition, but also an opsonin participating in the clearance of invaders in innate immunity. Moreover, the ability of CfC1qDC to interact with immunoglobulins provided a clue to understand the evolution of classical pathway in complement system.

A novel cold-regulated cold shock domain containing protein from scallop Chlamys farreri with nucleic acid-binding activity.

BACKGROUND: The cold shock domain (CSD) containing proteins (CSDPs) are one group of the evolutionarily conserved nucleic acid-binding proteins widely distributed in bacteria, plants, animals, and involved in various cellular processes, including adaptation to low temperature, cellular growth, nutrient stress and stationary phase. METHODOLOGY: The cDNA of a novel CSDP was cloned from Zhikong scallop Chlamys farreri (designated as CfCSP) by expressed sequence tag (EST) analysis and rapid amplification of cDNA ends (RACE) approach. The full length cDNA of CfCSP was of 1735 bp containing a 927 bp open reading frame which encoded an N-terminal CSD with conserved nucleic acids binding motif and a C-terminal domain with four Arg-Gly-Gly (RGG) repeats. The CSD of CfCSP shared high homology with the CSDs from other CSDPs in vertebrate, invertebrate and bacteria. The mRNA transcripts of CfCSP were mainly detected in the tissue of adductor and also marginally detectable in gill, hepatopancreas, hemocytes, kidney, mantle and gonad of healthy scallop. The relative expression level of CfCSP was up-regulated significantly in adductor and hemocytes at 1 h and 24 h respectively after low temperature treatment (P<0.05). The recombinant CfCSP protein (rCfCSP) could bind ssDNA and in vitro transcribed mRNA, but it could not bind dsDNA. BX04, a cold sensitive Escherichia coli CSP quadruple-deletion mutant, was used to examine the cold adaptation ability of CfCSP. After incubation at 17°C for 120 h, the strain of BX04 containing the vector pINIII showed growth defect and failed to form colonies, while strain containing pINIII-CSPA or pINIII-CfCSP grew vigorously, indicating that CfCSP shared a similar function with E. coli CSPs for the cold adaptation. CONCLUSIONS: These results suggest that CfCSP is a novel eukaryotic cold-regulated nucleic acid-binding protein and may function as an RNA chaperone in vivo during the cold adaptation process.

A novel scavenger receptor-cysteine-rich (SRCR) domain containing scavenger receptor identified from mollusk mediated PAMP recognition and binding.

Scavenger receptors (SRs) are significant endocytic receptors contributing to constant internal environment. SR-cysteine-rich (SRCR) domain-containing SR is the most important class of SRs which has been so far reported exclusively in mammals and birds. In the present study, a novel SRCR domain-containing SR (CfSR) was firstly identified from scallop Chlamys farreri. The full-length cDNA of CfSR was of 2639 bp encoding a polypeptide of 804 amino acids with a signal peptide, six SRCR domains, a UPAR-like domain and a ShK toxin-like domain. All the SRCR domains contain highly conserved six cysteine residues to form three pairs of intradomain disulfide, among which SRCR-D5 was assumed to participate in ligand-binding. An attachment site of sequence CTTPLCN was found in UPAR-like domain, indicating CfSR was an anchor protein. This prediction was confirmed by its localization on the outer surface of hemocytes with immunofluorescence assay. The mRNA expression of CfSR was up-regulated significantly by the stimulations of lipopolysaccharides, peptidoglycan and ß-glucan. A truncated CfSR (from V456 to T8°4) including SRCR-D5 was recombined and expressed in Escherichia coli, and the recombined protein displayed unique broad ligand-binding properties not only for acetylated low density lipoprotein (Ac-LDL) and dextran sulfate, but also for various pathogen associated molecular patterns, such as LPS, PGN, mannan and zymosan. All the results indicated that CfSR, the most primitive SR identified to date, was a versatile PRR involved in immune recognition, and the existence of functional SR might trace back to at least mollusk phylum.

The Gln32Lys polymorphism in HSP22 of Zhikong scallop Chlamys farreri is associated with heat tolerance.

BACKGROUND: Heat shock protein 22 is a member of small heat shock proteins with molecular chaperone activity. Though their multiple functions have been well characterized, there is no report about the association between the polymorphisms of HSP22 and heat tolerance. METHODOLOGY: Three single nucleotide polymorphisms were identified in HSP22 from scallop Chlamys farreri (CfHSP22), and the +94 C-A locus was found to be nonsynonymous. Three genotypes at locus +94, A/A, A/C and C/C, were revealed by using Bi-PASA PCR analysis, and their frequencies were 19.5%, 27.6% and 52.9% in the heat resistant stock, while 9.3%, 17.4% and 73.3% in the heat susceptible stock, respectively. The frequency differences of the three genotypes were significant (P<0.05) between the two stocks. After incubating at 30°C for 84 h, the cumulative mortality of scallops with +94 C/C genotype and +94 A/C genotypes was 95% and 90%, respectively, which was significantly higher (P<0.01) than that of scallops with +94 A/A genotype (70%). The molecular chaperone activity of two His-tagged fusion proteins, rCfHSP22Q with +94 C/C genotype and rCfHSP22K with +94 A/A genotype were analyzed by testing the ability of protecting citrate synthase (CS) against thermal inactivation in vitro. After incubated with rCfHSP22Q or rCfHSP22K at 38°C for 1 h, the activity of CS lost 50% and 45%, and then recovered to 89% and 95% of the original activity following 1 h restoration at 22°C, respectively, indicating that the mutation from Gln to Lys at this site might have an impact on molecular chaperone activities of CfHSP22. CONCLUSIONS: These results implied that the polymorphism at locus +94 of CfHSP22 was associated with heat tolerance of scallop, and the +94 A/A genotype could be a potential marker available in future selection of Zhikong scallop with heat tolerance.