The Eighth Annual National Biological Convention (ANBC)of Singapore Institute of Biology (SIBiol)

Oct 18 (Saturday), 2008 at the NUS Guild HousE (KEnt RidgE)

The ANBC programme is organized to showcase the latest research outputs and discoveries in biological sciences by members and invited guests. The yearly gathering is an educational experience as well as a rare opportunity for members to renew friendship and camaraderie.

In view of the current trend in biology education and research, we have lined up two talks on relevant topics in molecular biology, and two talks on plant (ginger group) and animal (lungless frog) diversity at organismal level. .

Programme

Sypnosis...

3:15-3:40 pm
Parkin gene, a novel suppressor of brain tumors

Calvin Wee Sing Yeo 1,5, Carol Soo Leng Tang 2, Beng Ti Ang 3, Kah Leong Lim 1,4,5

1 Neurodegeneration Research Lab, National Neuroscience Institute, Singapore; 2 Neuro-Oncology Research Lab, National Neuroscience Institute, Singapore; 3 Department of Neurosurgery, National Neuroscience Institute, Singapore; 4 Duke-NUS Graduate Medical School, Singapore; 5 Department of Biological Sciences, National University of Singapore

Abstract
Mutations in the Parkin gene, which encodes an ubiquitin ligase, were originally associated with the familial parkinsonism. Interestingly, the recent characterization of the common fragile site (CFS) FRA6E on chromosome 6q has determined that the Parkin gene localizes within the FRA6E region of instability. Notably, genes residing within CFSs are frequently involved in cancers. Following this discovery, Parkin gene alterations and expression variability were identified in a variety of tumor biopsies and cell lines representing a wide range of cancers including ovarian, breast, lung and liver cancers. Frequently, diminished or absent Parkin expression is observed in these cancers, suggesting that Parkin may have tumor suppression properties. Consistent with these findings, we found that the expression levels of Parkin mRNA and protein are dramatically down-regulated in glial tumor cell lines compared to control cell lines. Importantly, overexpression of Parkin in U87MG cells, a representative glial tumor cell line, significantly mitigates the rate of U87MG cell proliferation in vitro as well as reduces its ability to generate solid tumors in vivo. Moreover, overexpression of Parkin gene in both synchronized and unsynchronized U8MG cell line reduces the levels of phosporylated Akt, a pro-survival factor. Taken together, our findings support a negative role for Parkin in gliomagenesis.

3:40-4:05 pm
Deciphering and reconstruction of embryonic stem cell transcriptional regulatory network

Dr. Huck-Hui Ng
Genome Institute of Singapore, Singapore, and Department of Biological Sciences, NUS

Abstract
Transcription factors and their specific interactions with targets are crucial in specifying gene expression programmes. To gain insights into the transcriptional regulatory networks in embryonic stem cells, we use chromatin immunoprecipitation coupled to ultra-high-throughput DNA sequencing (ChIP-seq) to map the locations of multiple sequence specific transcription factors. These factors are known to play different roles in ES cell biology as components of signaling pathways, self-renewal regulators and key reprogramming factors. Our study provides new insights into the integration of the signaling pathways to the ES cell-specific transcription circuitries. Intriguingly, we find specific genomic regions extensively targeted by different transcription factors and these multiple transcription factors generally exhibit two major mode of targeting in ES cells. Collectively, the comprehensive mapping of transcription factor binding sites identifies new features of the transcriptional regulatory networks that define ES cell identity. Using this knowledge, we investigate nodes in the network which when activated, will jump-start the ES cell-specific expression program in somatic cells.

4:05-4:25 pm
The Amazing World of Gingers

Dr. Jana Skornickova
The Herbarium, Singapore Botanic Gardens

Abstract
Gingers (family Zingiberaceae) are perennial herbs, which play an important role in tropical rain forests and other various tropical vegetation types. Some of them are tiny, while the others reach up to 8 meters. Many are sources of spices, medicinal plants and ornamental plants. More than 50 genera with over 1,500 species are known worldwide with centre of their diversity in Asia. However the total number of genera and species is still uncertain and there are more than 3700 names of Zingiberaceae published, creating great chaos and hindering various research as well as conservation efforts. This pictorial talk will feature the amazing varieties and colours of this fascinating plant family in Asia and the world.

4:25-4:50 pm
The First Lungless Frog Discovered on Borneo

Dr. David Bickford 1, Djoko Iskandar 2 and Anggraini Barlian 2

1 Department of Biological Sciences, Faculty of Science National University of Singapore; 2 Institut Teknologi Bandung,10 Jalan Ganesa, Bandung, 40132 Java, Indonesia

Abstract
Lungs helped animals conquer terrestrial habitats and are one of the few defining characteristics for tetrapods (amphibians, reptiles, birds, and mammals). Here we report the first case of complete lunglessness in a frog, Barbourula kalimantanensis, from the Indonesian portion of Borneo. The loss of an evolutionary break-through occurs very rarely and only under extreme evolutionary and ecological conditions in nature. Lunglessness in tetrapods (amphibians, reptiles, birds, and mammals) is exceedingly rare, previously known only from one family of salamanders, one genus of salamanders, and a single species of caecilian. A recent expedition to central Kalimantan rediscovered two new populations of this enigmatic aquatic species of frog, previously only known from two specimens, enabling a more comprehensive assessment of the species’ ecology, anatomy, and physiology that led to the discovery of lunglessness. Loss of lungs in tetrapods has only been found in Amphibia, most likely due to their history at the interface between aquatic and terrestrial habitats and their ancient ability to respire through the skin. I will comment on the physiological requirements, habitat specificity, and extremely urgency of conserving remaining habitat that can support this species.

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