Profile

For the past eleven years at which I have been at AIU, I have strived to improve myself both as a Natural Science instructor and as a published researcher in the field of Plant Cell Biology. AIU students play a crucial role in my research, lending their hands, their minds, and their energy to my laboratory projects.

My Undergraduate Degree included a one year Industrial Placement with Glaxo R&D, (now GlaxoSmithKline) and it was during this time, working in the Image Analysis laboratory of the Molecular Science Department, that I developed my deep and enduring interest in Cell Biology and Microscopy. After graduating with a degree in Biochemistry from the University of York in 1996, I obtained my PhD in the laboratory of Jürgen Denecke using both Cell and Molecular Biology techniques to characterise a novel protein complex formed between the endoplasmic reticulum (ER) resident chaperones.

In April 2001 I left the UK for the US and entered the laboratory of Prof. Tom Okita in the Institute of Biological Chemistry at Washington State University. In the Okita lab I worked in a closely related field, - RNA localization of rice seed storage proteins, and was very fortunate to be able to work on many interesting and wide-ranging projects, and to explore and develop experience in a very broad range of experimental techniques. The majority of my efforts were focused on the identification and characterisation of a large number of novel prolamine mRNA binding proteins.

I came to Akita International University in August 2009 and since that time I have continued to pursue my research interests, both independently and through collaboration with Faculty at Akita Prefectural University, Kyushu University, Kyoto University, and Washington State University. At the same time, I have also greatly enjoyed the challenge of developing and offering Introductory lecture and laboratory courses for both Biology and Chemistry to meet the unique demands of liberal arts students studying at AIU.

Research Field

For more than fifteen years now, my research has been focused on understanding the process of RNA targeting in rice seeds. RNA targeting is a ubiquitous mechanism found in all branches of the tree of life which allows proteins to be synthesized at the appropriate intracellular locations. In rice this mechanism uniquely permits the sorting of two major classes of storage protein mRNAs to distinct sub-domains or regions of the cortical endoplasmic reticulum (ER).

This research, and the work I have done previously, involves a wide range of cellular and molecular biology techniques ranging from fluorescence microscopy, protein expression and purification, immunoprecipitation and proteomics through to next generation sequencing and data analysis. Although this research is basic and curiosity-driven in nature, it is anticipated that a better understanding of the process of RNA transport could give rise to increases in the productivity of this very important food crop.

Recent Activities

The main focus of my research efforts is currently a three year KAKENHI project funded by the JSPS. This project runs until April 2019 and aims to establish a connection between the processes of vesicular transport and RNA localisation. Understanding this process will likely have positive implications for improving the productivity of rice plants.

AIU students have played an important part in my research through their participation in my BIO 205 Science Research Project course and by working as Student Research Assistants.

Currently I am establishing new collaborative projects related to my work on RNA and protein targeting both within and outside Japan.

Recent publications:

1) Yang Y., Chou, H.L., Crofts, A.J., Zhang, L., Tian, L., Washida, H., Fukuda, M., Kumamaru, T., Oviedo, O.J., Starkenburg, S.R., and Okita, T.W. (2018). Selective sets of mRNAs localize to extracellular paramural bodies in a rice glup6 mutant. J. Exp. Bot., 69, 5045-5058.

2) Yang, Y., Crofts, A.J., Crofts, N., and Thomas W. Okita (2014). Multiple RNA binding protein complexes interact with the cis-localization RNA zipcode sequences of prolamine RNAs. Plant Physiol. 164, 1271-1282.

3) Doroshenk, K.A., Tian, L., Crofts, A.J., Kumamaru, T., and Okita, T.W. (2014). Characterization of the RNA binding protein RBP-P reveals a possible role in rice glutelin gene expression and RNA localization. Plant Mol. Biol. 85, 381-394.

4) Doroshenk, K.A., Crofts, A.J., Washida, H.W., Satoh-Cruz,M., Crofts, N., Yang, Y., Morris, R.T., Wyrick, J.J., Okita, T.W., Kumamaru, T., and Satoh, H. (2012). mRNA Localization in Plants and the Role of RNA Binding Proteins. RNA Binding Proteins. Zdravko Lorković, ed. (Landes Bioscience).

5) Doroshenk, K.A., Crofts, A.J., Morris, R.T., Wyrick, J.J., and Okita, T.W. (2012). RiceRBP: a resource for experimentally identified RNA binding proteins in Oryza sativa.. Frontiers in Plant Sci. 3, 1-6.

6) Fukuda M., Satoh-Cruz, M., Wen, L., Crofts, A.J., Sugino, A., Washida, H., Okita, T.W., Ogawa, M., Kawagoe, Y., Maeshima, M., and Kumamaru, T. (2011). The small GTPase Rab5a is essential for intracellular transport of proglutelin from the Golgi apparatus to the protein storage vacuole and endosomal membrane organization in developing rice endosperm. Plant Physiol., 157, 632-644.

7) Morris, R.T., Doroshenk, K.A., Crofts, A.J., Lewis, N., Okita, T.W. and Wyrick, J.J. (2011). RiceRBP: a database of experimentally identified RNA-binding proteins in Oryza sativa L. Plant Science, 180, 204-211.

8) Doroshenk, K.A.*, Crofts, A.J.*, Washida, H.W.*, Satoh-Cruz, M., Crofts, N., Okita, T.W., Morris, R.T., Wyrick, J.J., Fukuda, M., Kumamaru, T., and Satoh, H. (2010). Characterization of the rice glup4 mutant suggests a role for the small GTPase Rab5 in the biosynthesis of carbon and nitrogen storage reserves in developing endosperm. Breeding Science, 60, 556-567. * equal contribution

9) Satoh-Cruz, M.* Crofts A.J.*, Takemoto-Kuno, Y.*, Sugino, A., Washida, H., Crofts, N., Okita, T.W., Satoh, H., and Kumamaru, T. (2010). Protein disulfide isomerase like 1-1 participates in the maturation of proglutelin within the endoplasmic reticulum in rice endosperm. Plant Cell Physiol., 51, 1581-1593. * equal contribution

10) Crofts, A.J.*, Crofts, N.*, Whitelegge, J.P., and Okita, T.W. (2010). Isolation and identification of cytoskeleton-associated prolamine mRNA binding proteins from developing rice seeds. Planta, 231, 1261-1276. * equal contribution

Message to Students

Science is a hands-on subject and I firmly believe that performing scientific research can help students to develop the logical and critical thinking skills which are key elements of a liberal arts education. Science, especially lab work and field trips, can also be a lot of fun!

In addition to the introductory level natural science lecture and lab courses I give at AIU, I also offer a Science Research Project course (BIO205) in which students spend at least 5 hours per week in the lab and gain first-hand experience of real-world experimental scientific research. The main focus of my current research project is to investigate the mechanism of protein biosynthesis in rice seeds. Working on this project allows students to learn both the theory and application of biochemical and molecular biology techniques that are used in research labs throughout the world.

In scientific research, many small failures are a big part of any major success. Never underestimate the power of trial and error and realise that every mistake you make, in life as well as in science, is a learning opportunity. Just don't make the same mistake too many times!