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Investigates the phylogeny of primary-symbionts of species belonging to the subgeneral of Glossina based on 16S recombinant DNA sequences. Lineage of organisms in the gamma-subdivision of proteobacteria; Association of evolution with symbiosis; Evidence for the development of symbiosis acquisition by S-endosymbionts.

The present work reported the cloning and characterization of two novel human genes—HN1 (hematopoietic- and neurologic-expressed sequence 1) and HN1L (HN1-like gene) which are proposed to be involved in embryo development. HN1 is mapped on chromosome 17q25.2, with two transcripts (1.0 and 1.6 kb in length, respectively) due to alternative splicing. HN1 is expressed abundantly in testis and skeletal muscle among 16 human tissues, and it is localized in the nucleus indicated by GFP fusion expression. Western blot confirmed that HN1 encodes a 16.5-kDa protein. HN1L is on chromosome 16p13.3, with three splicing in the length of 2.0, 4.0 and 4.2 kb, respectively. HN1L is expressed in a variety of tissues such as liver, kidney, prostate, testis and uterus at varying levels. HN1L gene encodes a 20-kDa protein, which is localized in both the nucleus and cytoplasm. Fourteen of HN1 and sixteen of HN1L homologous genes in different species were determined and analyzed by BLAST searches. Silicon analyses of the 14 orthologous proteins of HN1 and 16 orthologous proteins of HN1L revealed that they share great conservation in vertebrate. Additionally, we identified nine pseudogenes of HN1 (six) and HN1L (three) in the genomes of the human, mouse and rat. Based on sequence alignments and phylogenetic analysis, all these homologous genes and pseudogenes were defined as a HN1 gene family. [Copyright &y& Elsevier]

A metalloprotease and disintegrin (ADAM) is a family of membrane-anchored proteins and all family members have a multi-domain structure containing a zinc metalloprotease domain and a disintegrin domain that may serve as an integrin ligand. Here we reported two novel mammalian transcripts of Adam23, named Adam23β and Adam23γ, to be involved in the development and functional activities of mammalian brains. Adam23γ was isolated from a 22-week human fetal brain cDNA library, using an EST homologous to Adam as a probe, and is 100% homologous to human Adam23 (Adam23α) except that it lacks a fragment of 91 bp near the C-terminal, thus it could not form obvious transmembrane domain. Adam23β was discovered while the diversity at the transmembrane domain (TM) was analyzed. Adam23β has a different sequence in the 91 nucleotides and thus encode different transmembrane domain. Adam23β and Adam23γ are mainly expressed in brain like Adam23α. RT-PCR experiments in mouse brain also detected the two isoforms, consistent with observation of Northern analysis of human RNAs. Furthermore, results of RT-PCR amplification of Adam23γ in mouse brains of different developmental stages revealed a developmentally regulated expression pattern: Adam23γ is expressed in embryonic and infant brain, and disappeared after the 10th postnatal day. This temporally changing expression pattern of Adam23γ suggests that ADAM23γ likely plays an important role in brain development. [Copyright &y& Elsevier]

We have identified two novel human SCAN domain genes ZNF396 and ZNF397, which are clustered within the region of chromosome 18q12. Three isoforms of ZNF396 transcript, 1.5, 2.5 and 3.9-kb, are expressed highly in liver. Four isoforms of ZNF397 transcript, 1.7, 2.5, 7.0 and 9.0-kb, are expressed in a variety of tissues, with varying levels. The SCAN-(C2H2)X genes encode two distinct proteins due to a unique alternative splicing mechanism. Both ZNF396-fu (full zinc fingers) and ZNF397-fu consist of a SCAN domain in the N-terminal region and many consecutive C2H2 zinc finger repeats in the C-terminal region. ZNF396-nf (no zinc fingers) and ZNF397-nf encode 210 and 198 amino acids, respectively, containing the SCAN domain only. ZNF396-fu, ZNF396-nf, ZNF397-fu or ZNF397-nf can homo-associate, while ZNF396-fu hetero-associates with ZNF396-nf, and ZNF397-fu hetero-associates with ZNF397-nf. ZNF396-nf and ZNF397-nf polypeptides are expressed diffusely in the cells, while ZNF396-fu and ZNF397-fu polypeptides target specifically to the nuclei. ZNF396-fu, ZNF396-nf and ZNF397-nf can repress reporter gene transcription, with ZNF397-nf having the strongest repression activity. Deletion analysis revealed that ZNF397-fu is a transcriptional activator without its nine zinc finger repeats. [Copyright &y& Elsevier]

Lambda-crystallin is a composition of lens in rabbit and hare. It contains the putative NAD- or FAD-binding domain, which is named as HCDH domain in 3-hydroxyacyl-CoA dehydrogenase. In our attempt to search for genes differentially expressed between liver cancer tissues and normal tissues, human CRYL1 (crystallin, lambda 1) was identified. It was downregulated in 58% of 60 Chinese HCC tissue samples. The putative protein encoded by CRYL1 shares 83% identity with rabbit lambda-crystallin and contains two HCDH domains. Interestingly, CRYL1 mRNA level is remarkably high in liver and kidney, while it is extremely low in peripheral blood leukocyte and thymus. The CRYL1mRNA levels in liver and kidney are about 1.6 and 1.2 times the total amount of that in other 14 tissues, respectively. Both the special expression pattern and the putative HCDH structure of CRYL1 suggested that the protein may be of the similar function of 3-hydroxyacyl-CoA dehydrogenase. To further understand the lambda-crystallin protein family, we cloned four novel mammalian homologs from mouse, rat, bovine and pig. The unrooted phylogenetic tree of this protein family including human and other 26 species was drawn to analyse their evolutionary relationship. In addition, human CRYL1 was mapped to chromosome 13q12.11 and mouse Cryl1 to chromosome 14 between marker D14Mit83 and D14Mit260. [Copyright &y& Elsevier]

Protein kinase A (PKA) and neuronal nitric oxide synthase (nNOS) are important signaling molecules. It is well known that PKA can specifically phosphorylate nNOS. But the underlying molecular mechanism is still obscure. Our data indicate that the protein inhibitor of nNOS (PIN) binds to protein kinase A inhibitors (PKIs), which suggests that PKIs, together with PIN, might mediate the phosphorylation of nNOS by PKA. [Copyright &y& Elsevier]

Neuronal calcium sensors (NCS) are important constituents in the intracellular signaling pathways. A novel human gene, NCS-1, was identified in the present study. Among the 16 human tissues examined, NCS-1 is expressed most abundantly in the brain. Among the brain regions, the expression level of NCS-1 in cerebral cortex is the highest, which is about six times higher than the average level of the whole brain and a hundred times higher than the spinal cord. In the 12 different anatomical regions of human brain, the expression level of NCS-1 is very high in the temporal lobe, occipital pole, frontal lobe, thalamus, amygdala and hippocampus; moderate in cerebellum, putamen, caudate nucleus; low in the medulla, substantia nigra and the lowest in corpus callosum. Our results suggest that NCS-1 in human brain might be involved in a variety of brain functions such as sensory processing, motor control, emotional control, learning and memory. [Copyright &y& Elsevier]

Studies the isolation and characterization of a potential transposable element from Wolbachia, a group of Rickettsia-like bacteria. Nucleotide structure of the transposable element; Genomic difference between Wolbachia and different cytoplasmic incompatibility phenotype.

MANSC (motif at N terminus with seven cysteines) is a novel domain with a well-conserved seven-cysteine motif that is present at the N terminus of membrane and extracellular proteins, including low-density lipoprotein receptor-related protein 11 (LRP-11), hepatocyte growth factor activator inhibitor 1 (HAI-1) and some uncharacterized proteins encoded by multicellular animals from Mollusca to Chordata. We postulate that the MANSC domain in HAI-1 might function through binding with hepatocyte growth factor activator and matriptase. [Copyright &y& Elsevier]