During development, the Notch receptor regulates many cell fate decisions by a signaling pathway that has been conserved during evolution. One positive regulator of Notch is Deltex, a cytoplasmic, zinc finger domain protein, which binds to the intracellular domain of Notch. Phenotypes resulting from mutations in deltex resemble loss-of-function Notch phenotypes and are suppressed by the mutation Suppressor of deltex [Su(dx)]. Homozygous Su(dx) mutations result in wing-vein phenotypes and interact genetically with Notch pathway genes. We have previously defined Su(dx) genetically as a negative regulator of Notch signaling. Here we present the molecular identification of the Su(dx) gene product. Su(dx) belongs to a family of E3 ubiquitin ligase proteins containing membrane-targeting C2 domains and WW domains that mediate protein-protein interactions through recognition of proline-rich peptide sequences. We have identified a seven-codon deletion in a Su(dx) mutant allele and we show that expression of Su(dx) cDNA rescues Su(dx) mutant phenotypes. Overexpression of Su(dx) also results in ectopic vein differentiation, wing margin loss, and wing growth phenotypes and enhances the phenotypes of loss-of-function mutations in Notch, evidence that supports the conclusion that Su(dx) has a role in the downregulation of Notch signaling.

SummaryChromosomal relationship between humans and dusky langurs (Trachypithecus obscurus, 2nϭ44) was established by chromosome painting using chromosome specific DNA probes of the human chromosome 1 and 19 which each gave hybridization signals on two non-homologous dusky langur chromosomes. The results show that the human chromosome 1 and 19 probes hybridized to three regions of dusky langur on the autosomes 6 and 8. The human chromosome 1 probe hybridized to one region on the dusky langur chromosome 6 and two regions on the dusky langur chromosome 8, where the human chromosome 19 probe hybridized with the same pattern but on different regions. Hybridization patterns of human painting probes on dusky langur, when compared with the data of other species in the same genus suggest that the alternating hybridization pattern of the conserved segments homologous to human chromosomes 1 and 19 on dusky langur chromosomes 6 and 8 is the result of the translocation followed by the pericentric inversion. Moreover, the present research also indicates that the dusky langur's chromosomes 6 and 8 have the same hybridization patterns as other Asian colobines. Key words Trachypithecus obscurus, Chromosome painting, Reciprocal translocations.The dusky langur (Trachypithecus obscurus) is also called the dusky leaf monkey belongs to the family Cercopithecidae, subfamily Colobinae. There are three groups of colobine monkeys: the colobus monkeys of Africa, the langurs and the odd-nosed monkeys of Asia. T. obscurus is a species of Asian langurs distributed throughout South-east Asia. However, it can be found only in the southern part of Thailand. The classification and taxonomy of colobines has not been yet settled and is subject to continued revisions (Napier and Napier 1967, 1985, Groves 1970, Oates et al. 1984, Vogel and Winkler 1990. For instance, there is no consensus even on the number of genera and species. The dusky langur is either classified in the genus Trachypithecus (Oates et al. 1984) or the genus Presbytis (Napier and Napier 1985). The scheme of Oates et al. (1984) was used as the classification system which put dusky langur into the genus Trachypithecus.In the previous studies using the classical staining, the diploid numbers of both African (genus Colobus) and Asian (genus Presbytis) colobines were demonstrated that they are to be 2nϭ44 (Chiarelli 1963, Ushima et al. 1964. All chromosomes can be divided into two groups; the metacentric and the submetacentric according to their centromeric index, with the exceptions that the Asian langurs have a pair of small acrocentric chromosomes while the African colobines have

SummaryHere we report natural autotetraploid and chromosomal characteristics in the subfamily Botiinae from Northeast Thailand. Kidney cell samples were taken from tiger botia (Syncrossus helodes), red-finned loach (Yasuhikotakai modesta), silver botia (Y. lecontei) and skunk botia (Y. morleti). The mitotic chromosome preparation was prepared directly from kidney cells. Conventional staining and Ag-NOR banding techniques were applied to stain the chromosomes. The results showed that the tetraploid chromosome numbers of S. helodes, Y. modesta, Y. lecontei and Y. morleti were 4n (natural autotetraploid)=100 for all species, and the fundamental numbers (NF) were 122 for all species. The presences of metacentric, submetacentric, and telocentric chromosomes were 12-10-78 for all species. No cytologically distinguishable sex chromosome was observed. The nucleolar organizer regions (NORs) were observed at the region adjacent to the short arms of a pair of submetacentric chromosome for all species. These results show the evolutionary relationship between species of loach fish from Thailand. The karyotype formula was deduced as:S

In present study, Loop Mediated Isothermal Amplification (LAMP) assay was conducted for diagnosis Nosema bombycis, the pebrine disease pathogen in domestic silkworm, Bombyx mori. Nine isolates of N. bombycis were collected from infected silkworms in rearing areas in Khon Kaen province, Thailand. N. bombycis genomic DNAs were extracted by boiling method and used as templates in LAMP and PCR reactions. A LAMP primer set was designed specific to N. bombycis small subunit ribosomal RNA (SSU rRNA) gene. The results revealed that the optimal condition was constantly performed at 63oC for 1 hour. The product was directly visualized by naked eye and confirmed with agarose gel eletrophoresis. LAMP assay is more sensitive than traditional PCR, since LAMP was able to detect the least 10 spores/ml while PCR needs 100 spores/ml. In addition, the present novel LAMP primer set was specific only to N. bombycis proven by the negative results when other B. mori pathogen DNAs were tested. In conclusion, the LAMP assay demonstrated a great potential alternative method in diagnosis N. bombycis with high sensitivity, rapidity and accuracy which can apply for pebrine disease surveillance.

Abstract. Prakrongrak N, Boonsoong B, Monthatong M. 2023. Genetic diversity and phylogenetic analysis of mayfly Caenis (Insecta: Ephemeroptera) using Cytochrome C Oxidase I (COI) and 12s rRNA genes from Thailand. Biodiversitas 24: 1989-1997. Mayflies in genus Caenisis one of the top fifth species richnessbelonged to Family Caenidae. The present study aimed to use the partial mitochondrial Cytochrome COxidase subunit I (COI) and 12s rRNA nucleotide sequences for molecular species identification, diversity and phylogenetic relationships of mayflies in genus Caenis Stephens, 1835 species from Thailand. From a total of 37 specimens, thirteen nymphs were morphologically identified into five species: Caenis nasuta Malzacher, C. Picea Kimmins, C. ulmeriana Malzacher, C. cornigera Kang and Yang and C. longiforcipata Malzacher. The other 24 samples were Caenis sp.1 to sp.5. Partial COI sequences of all samples were compared with BOLD and GenBank for species identification. However, the result showed only genus-level identification as Caenis with greater than 80% similarity. For species delimitation, interspecific genetic distance among these species ranged from 14.4 to 26.6% (COI) and from 7.36 to 22.4% (12s rRNA). Intraspecific divergence levels were 0.0% to 2.35%. ABGD analysis of both genes divided data into 10 groups corresponding to 10 morphospecies of Caenis. The phylogenetic relationships of Caenis, COI and 12s rRNA genes also classified each species to well supported clusters. In addition, we report C. cornigera from Thailand for the first time. The COI and 12s rRNA phylogenetic trees indicate a close relationship between C. cornigera and C. longiforcipata, which is supported by their similar morphology.