Update Date: February 10, 2009

The ZS Editorial Board (Chairperson: Yoshitaka Nagahama, Member) recommended candidates for the 2005 Paper Award to the Board of Councillors, and following deliberation, the Board of Councillors selected the following four papers for the 2005 Paper Award.

(1) Inoue,T,Kumamoto,H,Okamoto,K,Umesono,Y,Sakai,M,Alvarado,S.A,Agata,K.
Morphological and Functional Recovery of the Planarian Photosensing System during Head Regeneration
Zool. Sci. 2004, 21 (3): 275-283.
Reason for recommendation: This paper utilizes the fact that planarians exhibit negative phototaxis, that this behavior is lost when the head is amputated, and that the head regenerates within five days along with the recovery of negative phototaxis, attempting to elucidate the process of neural circuit formation in planarians and the molecular functions involved using the RNAi method. It is a well-crafted piece of work that makes skillful use of phenomena and techniques spanning multiple fields.

(2) Umezu, T and Tomooka, Y
Evidence of stromal cell populations functionally linked with epithelial cell populations in the mouse oviduct.
Zool. Sci. 2004, 21 (3): 319-326
Reason for recommendation: This paper analyzes epithelial-stromal cell interactions using mouse oviduct-derived cell lines. The authors established several cell lines of oviductal epithelial and stromal cells and analyzed the inductive effects of stromal cells using gene expression in epithelial cells as an indicator. The results suggest that stromal cells may regulate gene expression in epithelial cells via diffusible factors. This is an ambitious study and a valuable achievement that serves as a foundation for analyzing the molecular mechanisms of epithelial-stromal cell interactions. On the other hand, the content also suggests that the stroma is composed of diverse cell types, thereby providing a novel concept. With high academic content and expected spillover effects into a wide range of fields, this paper is considered worthy of the ZS Award.

(3) Kobayashi,Y,Kobayashi,T,Nakamura,M,Sunobe,T,Morrey,C.E,Suzuki,N,Nagahama,Y.
Characterization of two types of cytochrome P450 aromatase in the serial-sex changing gobiid fish, Trimma okinawae
Zool. Sci. 2004, 21(4): 417-425
Reason for recommendation: Using the Okinawa ruby goby (Trimma okinawae), a rare bidirectional sex-changing goby, this paper cloned the gene for cytochrome P450 aromatase (P450arom), which is essential for elucidating the sex change mechanism, and determined its full-length sequence. It revealed the existence of two types of P450arom in this goby, A and B, and demonstrated that both possess P450arom enzyme activity using a eukaryotic expression system. Furthermore, it elucidated the localization of P450aromA, which shows high expression, within the ovaries and testes. In addition, it revealed that P450aromA expression in the ovaries fluctuates across the ovarian cycle. All of these research findings are novel and serve as an important foundation for elucidating the sex change mechanism. For these reasons, we recommend this paper as fitting for the Zoological Science Award.

(4) Tadashi Akiyama
Entrainment of the circatidal swimming activity rhythm in the cumacean Dimorphostylis asiatica (Crustacea) to 12.5-hour hydrostatic pressure cycles.
Zool.Sci.2005,21(1):29-38.
Reason for recommendation: Unlike circadian rhythms, for which physiological mechanisms have become increasingly clear, research on the mechanisms of tidal rhythms is lagging behind. This paper elucidates the entrainment mechanism of tidal rhythms using water pressure as a zeitgeber by applying sinusoidal water pressure changes close to natural tidal fluctuations. Furthermore, by simultaneously applying a light-dark cycle, the activity observed exclusively during the dark phase in the field was successfully reproduced. This is the result of a long-standing challenge in an unexplored field where methodologies have not yet been established, and it can be evaluated as a landmark paper in chronobiology.