Hawley Lab

Bio
Before joining the Hawley Lab in 2002, Youbin worked on crop plants such as rice, barley and vegetables (Brassica campestris ssp. Parachinensis). He made the first strain of transgenic rice in China in 1998. In October 1998, Youbin started his post-doctoral work in Donald Weeks’ lab at University of Nebraska-Lincoln, where he worked on a single cell green algea (Chlamydomonas reinhardtii) to study carbon concentration mechanism (CCM). He used a CCM mutant to screen an index genomic library, and found and characterized a major CCM regulator, Cia5.

In the Hawley lab, Youbin has worked primarily on worked on achiasmate chromosome segregation. In 2006, he published a critical paper on the role of euchromatic crossover events in mediating heterochromatic associations. He then characterized the role of a polo kinase inhibitor, Matrimony, in mediating achiasmate (non crossover) chromosome segregation and cell cycle progression in female meiosis. He also established planania (Schmidtea mediterranea) as a modern system for the analysis of meiosis. He discovered that the clustering telomeres initiates SC formation and SC extension that mediates full-length chromosome pairing in this planarian spermatocytes.

Perhaps most significantly, Youbin used his experience in establishing new organism for meiotic study to reopen the study of SC formation and function in silkworm (Bombyx mori) oocytes. First described by Rasmussen in the 1970s, these oocytes create gigantic variants of SC structure that ensure homolog exchange in the absence of crossing over. In collaboration with Fengli Guo from the Stowers Institute imaging facility, Youbin has re-started Rasmussen’s innovative study of Bombyx meiosis by using both high resolution microscope and modern techniques for protein localization. ‍

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Relevant Publications
Synaptonemal complex extension from clustered telomeres mediates full-length chromosome pairing in Schmidtea mediterranea.
Xiang Y, Miller DE, Ross EJ, Sanchez Alvarado A, Hawley RS. Proc Natl Acad Sci U S A. 2014;111:E5159-E5168.  
‍Original Data

Mutations in the chromosomal passenger complex and the condensin complex differentially affect synaptonemal complex disassembly and metaphase I configuration in Drosophila. female meiosis
Resnick TD, Dej KJ, Xiang Y, Hawley RS, Ahn C, Orr-Weaver TL. Genetics. 2009;181:875-887.

The Inhibition of Polo Kinase by Matrimony Maintains G2 Arrest in the Meiotic Cell Cycle  
Xiang Y, Takeo S, Florens L, Hughes SE, Huo LJ, Gilliland WD, Swanson SK, Teeter K, Schwartz JW, Washburn MP, Jaspersen SL, Hawley RS. PLoS Biol.2007;5:2831-2846.

The Mechanism of Secondary Nondisjunction in Drosophila melanogaster Females
Xiang Y, Hawley RS. Genetics.2006;174:67-78.

Analyses of CIA5, the master regulator of the carbon-concentrating mechanism in Chlamydomonas reinhardtii, and its control of gene expression.
Ying Wang, Zhaohui Sun, Kempton M Horken,Chung-Soon Im, Youbin Xiang, Arthur R Grossman, and Donald P Weeks.  (2005) Canadian Journal of Botany.  https://doi.org/10.1139/b05-062

Chemiluminescent-based methods to detect subpicomole levels of c-type cytochromes.
Robert Feissner,  Youbin Xiang, Robert GKranz. (2003)  Analytical Biochemistry 315(1):90-4. DOI:10.1016/S0003-2697(02)00658-9

Selenoproteins and selenocysteine insertion system in the model plant cell system, Chlamydomonas reinhardtii.
Sergey V. Novoselov, Mahadev Rao, Natalia V.Onoshko, Huijun Zhi, Gregory V. Kryukov, Youbin Xiang, Donald P. Weeks, DolphL. Hatfield, Vadim N. Gladyshev. (2002) EMBO J 21:3681-3693.https://doi.org/10.1093/emboj/cdf372

The Cia5 gene controls formation of the carbon concentrating mechanism in Chlamydomonas reinhardtii.
Youbin Xiang, Jun Zhang, and Donald P. Weeks.(20010  PNAS  98 (9) 5341-5346.  https://doi.org/10.1073/pnas.101534498

Transgenic rice plants with a synthetic cry1Ab gene from Bacillus thuringiensis were highly resistant to eight lepidopteran rice pest species
Qingyao Shu, Gongyin Ye, HairuiCui, Xiongying Cheng, Youbin Xiang, Dianxing Wu, Mingwei Gao, Yingwu Xia, CuiHu, Ravinder Sardana, Illimar Altosaar. (2000)  Molecular Breeding 6:433–439. DOI:10.1023/A:1009658024114

Agrobacterium-mediated transformation of Brassica campestris ssp. Parachinensis with synthetic Bacillus thuringiensis cry1Ab andcry1Ac genes.  
Y. Xiang,  W.-K.R. Wong,   M.C. Ma, R.S.C. Wong.  (2000) Plant Cell Reports 19(3):251-256.  DOI:10.1007/s002990050007

Agrobacterium mediated Transformation of Insecticidal Bacillus thuringiensis cryIA(b) and cryIA(c) Genes and Their Expression in Rice.
Youbin Xiang, Zhuqing Liang, Mingwei Gao,  Qingyao Shu,  Gongyin Ye, Xiongying Cheng, Altosaar  Illimar. (1998) Chinese Journal of Biotechnology.  15(4):494-500