Cylindrotheca closterium Is a Species Complex as Was Evidenced by the Variations of rbcL Gene and SSU rDNA

The genus Cylindrotheca consists of a small group of marine diatoms with a few species described. Eleven isolates of diatoms identified as Cylindrotheca closterium morphologically were obtained from Jiaozhou Bay with their nuclear-encoded small-subunit ribosomal RNA （SSU rDNA） and chloroplast-encoded rbcL gene sequences determined in this study. Interestingly, very high sequence divergences of SSU rDNA and rbcL gene were found among these isolates, and numerous nucleotide variation of rbcL gene caused relatively few variation of deduced amino acid sequence. Phylogenetic analyses based on SSU rDNA and rbcL gene, respectively, grouped the isolates into 6 clades. Phylogenetic tree of SSU rDNA placed all the Cylindrotheca isolates together, separating them into two lineages clearly. LineageⅠ was composed of the eleven C. closterium isolates obtained in this study together with another C. closterium isolate, but some clades were not well supported. LineageⅠwas contained two C. closterium isolates and one C. fusiformis isolate. Phylogenetic analysis of rbcL gene also separated the Cylindrotheca isolates into two well-defined lineages. The eleven C. closterium isolates formed a lineage and all clades were supported strongly. Statistical comparisons of SSU rDNA indicated that the average distance within lineageⅠwas significantly higher than that of other microalgae species （P 〈0.01）. These results suggested the existence of cryptic species within C. closterium.

Genome-wide survey and analysis of microsatellites in the Pacific oyster genome: abundance, distribution, and potential for marker development

Microsatellites are a ubiquitous component of the eukaryote genome and constitute one of the most popular sources of molecular markers for genetic studies. However, no data are currently available regarding microsatellites across the entire genome in oysters, despite their importance to the aquaculture industry. We present the fi rst genome-wide investigation of microsatellites in the Pacifi c oyster Crassostrea gigas by analysis of the complete genome, resequencing, and expression data. The Pacifi c oyster genome is rich in microsatellites. A total of 604 653 repeats were identifi ed, in average of one locus per 815 base pairs(bp). A total of 12 836 genes had coding repeats, and 7 332 were expressed normally, including genes with a wide range of molecular functions. Compared with 20 different species of animals, microsatellites in the oyster genome typically exhibited 1) an intermediate overall frequency; 2) relatively uniform contents of(A)n and(C)n repeats and abundant long(C)n repeats(≥24 bp); 3) large average length of(AG)n repeats; and 4) scarcity of trinucleotide repeats. The microsatellite-fl anking regions exhibited a high degree of polymorphism with a heterozygosity rate of around 2.0%, but there was no correlation between heterozygosity and microsatellite abundance. A total of 19 462 polymorphic microsatellites were discovered, and dinucleotide repeats were the most active, with over 26% of loci found to harbor allelic variations. In all, 7 451 loci with high potential for marker development were identifi ed. Better knowledge of the microsatellites in the oyster genome will provide information for the future design of a wide range of molecular markers and contribute to further advancements in the fi eld of oyster genetics, particularly for molecular-based selection and breeding.

Assessment of genetic diversity by simple sequence repeat markers among forty elite varieties in the germplasm for malting barley breeding

The genetic diversity and relationship among 40 elite barley varieties were analyzed based on simple sequence repeat （SSR） genotyping data. The amplified fragments from SSR primers were highly polymorphic in the badey accessions investigated. A total of 85 alleles were detected at 35 SSR loci, and allelic variations existed at 29 SSR loci. The allele number per locus ranged from 1 to 5 with an average of 2.4 alleles per locus detected from the 40 badey accessions. A cluster analysis based on the genetic similarity coefficients was conducted and the 40 varieties were classified into two groups. Seven malting barley varieties from China fell into the same subgroup. It was found that the genetic diversity within the Chinese malting barley varieties was narrower than that in other barley germplasm sources, suggesting the importance and feasibility of introducing elite genotypes from different origins for malting barley breeding in China.

Adoptive transfer of T cells transduced with a chimeric antigen receptor to treat relapsed or refractory acute leukemia: efficacy and feasibility of immunotherapy approaches

Treatment outcomes of acute leukemia(AL) have not improved over the past several decades and relapse rates remain high despite the availability of aggressive therapies. Conventional relapsed leukemia treatment includes second allogeneic hematopoietic stem cell transplantation(allo-HSCT) and donor lymphocyte infusion(DLI), which in most cases mediate, at best, a modest graft-versus-leukemia effect, although their clinical efficacy is still limited. Although allo-HSCT following myeloablative conditioning is a curative treatment option for younger patients with acute myeloid leukemia(AML) in a first complete remission(CR), allo-HSCT as a clinical treatment is usually limited because of treatment-related toxicity. The overall DLI remission rate is only 15%–42% and 2-year overall survival(OS) is approximately 15%–20%, with a high(40%–60%) incidence of DLI-related graft-versus-host disease(GVHD). Therefore, development of new, targeted treatment strategies for relapsed and refractory AL patients is ongoing. Adoptive transfer of T cells with genetically engineered chimeric antigen receptors(CARs) is an encouraging approach for treating hematological malignancies. These T cells are capable of selectively recognizing tumor-associated antigens and may overcome many limitations of conventional therapies, inducing remission in patients with chemotherapy-refractory or relapsed AL. In this review, we aimed to highlight the current understanding of this promising treatment modality, discussing its adverse effects and efficacy.

Functional modules with disease discrimination abilities for various cancers

Selecting differentially expressed genes(DEGs) is one of the most important tasks in microarray applications for studying multi-factor diseases including cancers.However,the small samples typically used in current microarray studies may only partially reflect the widely altered gene expressions in complex diseases,which would introduce low reproducibility of gene lists selected by statistical methods.Here,by analyzing seven cancer datasets,we showed that,in each cancer,a wide range of functional modules have altered gene expressions and thus have high disease classification abilities.The results also showed that seven modules are shared across diverse cancers,suggesting hints about the common mechanisms of cancers.Therefore,instead of relying on a few individual genes whose selection is hardly reproducible in current microarray experiments,we may use functional modules as functional signatures to study core mechanisms of cancers and build robust diagnostic classifiers.

Augmenting the conservation value of rehabilitated wildlife by integrating genetics and population modeling in the post-rehabilitation decision process

Insular populations are particularly vulnerable to the effects of stochastic events, epidemics, and loss of genetic diversity due to inbreeding and genetic drift. The development of successful man- agement options will require accurate baseline data, establishment of clear objectives, and finally monitoring and implementation of corrective measures, if and when required. This study assessed management options for the genetic rehabilitation of highly inbred woylies obtained from wildlife rehabilitation centers. The study generated genetic data for the woylie Bettongia penicillata from a conservation reserve and calculated measures of genetic diversity and individual relatedness. These data were fed into a population viability analysis （PVA） to test genetic outcomes in relation to different management actions. We demonstrated that a careful selection of the founder cohort produced a population with an expected heterozygosity of -70% for a window of approximately 10 years. A proposal to increase the size of the reserve available to the colony was shown to almost double the time at which the colony would retain heterozygosity levels of≥70%. Additionally, developing a regular program of supplementation of unrelated woylies would result in a further improvement in their genetic value. This study demonstrated how the application of molecular techniques in combination with PVA can be beneficial for the management of rehabilitated wildlife otherwise considered of little conservation value. This approach can be applied to the management of breeding programs, but also to small, closed populations such as those found on islands, fenced enclosures, insurance populations, and in zoological collections.