Peritrophin, one of the components of the peritrophic matrix, was first isolated from the intestine of insects. It is thought to protect insects from invasion of microorganisms and to stimulate digestion of food. Peritrophin-like proteins have also been found in crustaceans, as a component of the egg layer. In this study, one fragment of the peritrophin-like gene was obtained from fleshy prawn (Chinese shrimp) (Fenneropenaeus chinensis) by panning the T7 phage display library constructed with the shrimp hemocyte cDNA. The total sequence of the peritrophin cDNA was cloned by modified SMART cDNA and LD-PCR methods. The full cDNA is 1048 bp and the deduced protein is composed of 274 amino acids, including 21 amino acid signal peptide, and four peritrophin A domains and the latter three forming three chitin-binding domains. Similarity analysis results showed that the peritrophin-like protein from F. chinensis has significant similarities with peritrophin-like and cortical rod proteins from other shrimp. It was inducing expression in hemocytes, heart, stomach, gut, and gills of the infected shrimp, and constitutive expression in the ovaries. No expression signal was detected in the hepatopancreas of either infected or noninfected shrimp. The recombinant peritrophin-like protein has the activity of binding Gram-negative bacteria and strong binding activity to chitin. Therefore, the bacteria and chitin binding activities of the peritrophin-like protein suggest that it may plays a role in immune defense and other physiological resposes.

Different cytogenetic techniques were used to analyze the chromosomes of white-bellied rat, Ni i enter confucianus from Mt. Tai and Jinan, Shandong Province and Ningshan, Shaanxi Province of China. Shandong populations have 2n=46 chromosomes with 4 metacentric, 2 subtelocentric, 16 telocentric pairs of autosomes and the submetacentric X and telocentric Y. The chromosomal arm number (NF) of the two populations was 56. Shaanxi population has 2n=46 chromosomes with 4 metacentric, 1 submetacentric, 1 subtelocentric and 16 telocentric pairs of autosomes and the submetacentric X and telocentric Y. The karyotype of Ningshan population showed NF=58. As the result of the comparison of C-and G-banding patterns, and compare with other species in the genus Ni i enter, we suppose that the chromosomal evolution of Ni i enter involved in pericentric inversion and heterochromatin growth. The submetacentri chromosomes of Shaanxi population would be originated from the growth of heterochromatin of the subtelocentric chromosome of Shandong population.

The mitotic and meiotic chromosomes of mandarin vole, Microtus mandarinus Milne-Edwards, from Shandong Province of China were analyzed by conventional, G-and C-banding and Silver-staining techniques. We detected chromosomal polymorphism in the vole, exhibiting diploid chromosome numbers 2n=48–50 and variable morphology of the 1st pair, one medium sized telocentric pair and the X chromosomes. Four types of karyotypes were revealed in the population. According to banding analysis, there were pericentric inversion, Robertsonian fusion and translocation in M. mandarinus karyotype evolution. The X displayed two different morphologies, which could be explained by prericentric inversion and a telocentric autosome translocation.

Pattern recognition proteins (PRPs), such as lipopolysaccharide and-1,3-glucan binding protein (LGBP), have been identified in many animals and play a crucial role in invertebrate defense systems. In the current study, an LGBP gene was cloned from fleshy prawn (Fenneropenaeus chinensis, Fc-LGBP) utilizing homology cloning and RACE methods. The full cDNA of the Fc-LGBP gene in fleshy prawn was 1253 bp in size with a deduced 366 amino acid protein that includes a glycosyl hydrolase domain. Northern blot and RT-PCR data suggested that Fc-LGBP mRNA was mostly synthesized in haemocytes and that the expression was down-regulated 24 h post-injection of bacteria. In situ hybridization demonstrated that Fc-LGBP mRNA was only detected in haemocyte cytoplasm, with no detection in other tissues. The molecular weight of the purified recombinantly expressed Fc-LGBP was approximately 46 kDa. Immunohistochemistry of haemocytes revealed that Fc-LGBP protein was localized on the membrane of most cells. Data from bacterial binding assays utilizing purified protein suggested that rFc-LGBP had strong binding activity to Gram-negative bacteria.

Thrombospondins (TSPs) are extracellular, multidomain, calcium-binding glycoproteins that modulate cell behavior in homeostasis and during development, wound-healing, immune response and tumor growth of adult tissues in vertebrates. In invertebrates these proteins are a major component of cortical rods in mature oocytes.Afragment of a thrombospondin-like genewas generated by screening a subtractive cDNA library constructed from the hemocytes of Chinese shrimp, Fennerpenaeus chinensis. The full length F. chinensis cDNA of thrombospondin was cloned by 3-and 5-rapid amplification of cDNA ends (3-and 5-RACE). The complete cDNA sequence, named Fc-TSP, is 2886 bp and the open reading frame of the cDNA encodes a 938-residue protein that contains three ChtBD2 domains, an EGF domain, a TSP-3 domain and a common TSP-C (CTD) domain. The protein shares a high sequence identity with the mj-TSPa (46.3%), mj-TSPb (46.9%) and mj-TSPc (51.9%) of Marsupenaeus japonicus. The expression and distribution of Fc-TSP in both challenged and unchallenged shrimps were studied by Northern blot, RT-PCR and in situ hybridization. Northern blot analysis showed that the Fc-TSP transcripts were detected in the hemocytes, heart, intestine, stomach and ovary of both challenged and unchallenged shrimps, but the signal was much stronger in the challenged tissues. A strong hybridization signalwas detected only in challenged hepatopancreas, with no signal in the unchallenged tissue. TheRT-PCR showed that the Fc-TSP was detected in both challenged and unchallenged tissues including the hemocytes, heart, hepatopancreas, stomach, gills, intestine, spermary and ovary. Except for the ovary and spermary, the signal of challenged tissues was relatively stronger than that of unchallenged ones, especially in hepatopancreas. These results suggest that the thrombospondin was upregulated in the hemocytes, heart, intestine and stomach of challenged shrimp, and induced in the hepatopancreas of challenged shrimps. Therefore, Fc-TSP may be involved in the defense responses of the shrimp.