Biomedical subjects

Ying Lai

Publications and source records attributed to Ying Lai.

3 recordsLinked to original sources

PubMed2005

Microarray analysis reveals similarities and variations in genetic programs controlling pollination/fertilization and stress responses in rice (Oryza sativa L.).

Previously, we identified 253 cDNAs that are regulated by pollination/fertilization in rice by using a 10K cDNA microarray. In addition, many of them also appeared to be involved in drought and wounding responses. To investigate this relationship, we obtained their expression profiles after dehydration and wounding treatments in this study. Venn diagram analysis indicated that 53.8% (136/253) and 21% (57/253) of the pollination/fertilization-related genes are indeed regulated by dehydration and wounding, respectively, and nearly half of the genes expressed preferentially in unpollinated pistils (UP) are responsive to dehydration. These results indicated that an extensive gene set is shared among these responses, suggesting that the genetic programs regulating them are likely related. Among them, the genetic network of water stress control may be a key player in pollination and fertilization. Additionally, 39.5% (100/253) cDNAs that are related to pollination/fertilization appear not to be regulated by the stress treatments (dehydration and wounding), suggesting that the existence of additional genetic networks are involved in pollination/fertilization. Furthermore, comparative analysis of the expression profiles of the 253 cDNAs under 18 different conditions (various tissues, treatments and developmental status) revealed that the genetic networks regulating photosynthesis, starch metabolisms, GA- and defense-responses are involved in pollination and fertilization. Taken together, these results provided some clues to elucidate the molecular mechanisms of pollination and fertilization in rice.

Cluster Analysis↗

PubMed2004

Monitoring of gene expression profiles and isolation of candidate genes involved in pollination and fertilization in rice ( Oryza sativa L.) with a 10K cDNA microarray.

To monitor gene expression profiles during pollination and fertilization in rice at a genome scale, we generated 73,424 high-quality expressed sequence tags (ESTs) derived from the green/etiolated shoot and pistil (0-5 h after pollination, 5hP) of rice, which were subsequently used to construct a cDNA microarray containing ca. 10 000 unique rice genes. This microarray was used to analyze gene expression in pistil unpollinated (UP), 5hP and 5DAP(5 days after pollination), anther, shoot, root, 10-day-old embryo (10EM) and 10-day-old endosperm (10EN). Clustering analysis revealed that the anther has a gene-expression profile more similar to root than to pistil and most pistil-preferentially expressed genes respond to pollination and/or fertilization. There are 253 ESTs exhibiting differential expression (e +/- 2-fold changes) during pollination and fertilization, and about 70% of them can be assigned a putative function. We also recovered 20 genes similar to pollination-related and/or fertility-related genes previously identified as well as genes that were not implicated previously. Microarray and real-time PCR analyses showed that the array sensitivity was estimated at 1-5 copies of mRNA per cell, and the differentially expressed genes showed a high correlation between the two methods. Our results indicated that this cDNA microarray constructed here is reliable and can be used for monitoring gene expression profiles in rice. In addition, the genes that differentially expressed during pollination represent candidate genes for dissecting molecular mechanism of this important biological process in rice.

Cluster Analysis↗

PubMed2002

Sequence and analysis of rice chromosome 4.

Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O. sativa, one of the first two rice chromosomes to be sequenced completely. The finished sequence spans 34.6 Mb and represents 97.3% of the chromosome. In addition, we report the longest known sequence for a plant centromere, a completely sequenced contig of 1.16 Mb corresponding to the centromeric region of chromosome 4. We predict 4,658 protein coding genes and 70 transfer RNA genes. A total of 1,681 predicted genes match available unique rice expressed sequence tags. Transposable elements have a pronounced bias towards the euchromatic regions, indicating a close correlation of their distributions to genes along the chromosome. Comparative genome analysis between cultivated rice subspecies shows that there is an overall syntenic relationship between the chromosomes and divergence at the level of single-nucleotide polymorphisms and insertions and deletions. By contrast, there is little conservation in gene order between rice and Arabidopsis.

Arabidopsis↗