Mammalian spermatogenesis takes place in the seminiferousepithelium, which is composed of Sertoli cells and germ cells. The interaction between spermatogenic and Sertoli cells as well as elongated spermatids and Sertoli cells is tightly regulated by junctional adhesion molecules (JAMs). JAMs, which are cell adhesion molecules, are known to play roles in various biological processes such as fertilization, neurogenesis, cancer progression, and spermatogenesis. Members of the JAM family have a unique structure: they contain an N-terminal signal peptide domain, immunoglobulin (Ig)-like domains, transmembrane and cytoplasmic tail domains, each of which has distinct functions. The extracellular Ig-like domains interact in a homophilic or heterophilic manner, whereas cytoplasmic tail domain mediates the tight junction assembly. Although members of the JAM family are exclusively present in or restricted to the testis, their precise roles in spermatogenesis and fertilization have not yet been completely explored. The functional roles of Nectin-2, Nectin-3, JAM-C, cell adhesion molecule1 (CADM1), coxsackie and adenovirus receptor (CAR) have been evaluated by analysis of null mutant mice. Unfortunately, CAR-deficient mice had an embryonic lethal phenotype; this demonstrates the importance of CAR in development, but its physiological role in spermatogenesis is not known. The loss of CADM1, Nectin-3 and JAM-C resulted in male infertility caused by loss of adhesion between germ and Sertoli cells. A variety of JAMs participate in the interaction between germ and Sertoli cells. Recently, human VSIG1 has been characterized, which was originally known as A34, as a new member of the JAM family; VSIG1 is composed of two extracellular Ig-like domains, a transmembrane domain, and a cytoplasmic domain. However, this molecule has not been functionally characterized, so this was one of the aims of our present study. RT-PCR and immunoblot analyses were used to study VSIG1 expression, VSIG1 was specifically expressed in testicular germ cells but not in sperm. Pull-down assay with glutathione S-transferase (GST) or His-fused first Ig and second Ig domains of VSIG1 and SDS-PAGE under mild non-reducing conditions demonstrated that VSIG1 functions as an in vitro homophilic adhesion molecule. Furthermore, cells expressing a deletion of the C-terminus of VSIG1 failed to interact with ZO-1, the central structural protein of the tight junction. These findings suggest mouse VSIG1 interacts with an unknown molecule in Sertoli cells via its extracellular domain, while its cytoplasmic domain is needed for binding to ZO-1. Thus, we suggest mouse VSIG1 may play an important role in spermatogenesis rather than fertilization by forming heterophilic complex with a molecule similar to JAM family.

아가리쿠스버섯에서 분리한 단백다당류를 분무건조한 분말의 저장안정성을 알아보기 위하여 저장 중 흡습특성을 조사하였다. 평형수분함량은 수분활성도가 높아짐에 따라 빠르게 증가하는 양상이었으며, 높은 온도에서 낮은 함량을 나타내었다. 단분자층 수분함량은 BET식보다 GAB식이 높은 유의성을 나타내었다. 수분활성도가 증가함에 따라 필요로 하는 흡습에너지가 낮아져 흡습엔탈피는 감소하여 흡습이 쉽게 이루어짐을 알수 있었다. 등온흡습곡선의 적합도는 Kuhn과

BPES(Blepharophimosis/Ptosis/Epicanthus inversus Syndrome)는 FOXL2 유전자의 돌연변이에 의해 유발되는 상염색체 우성질환이다. 눈꺼풀이 갈라지거나 쳐지고 넓은 미간이 나타나는 특징이 있으며, 여성의 조기 난소 부전증(prema-ture ovarian failure, POF)을 일으켜 불임을 유발한다. FOXL2는 forkhead family에 속하는 전사인자로서 FOXL2가 결여된 난소에서는 granulosa cell의 분화가 진행되지 않아 난포 성숙과정의 멈춤과 난자의 폐쇄증을 유발한다. FOXL2를 bait로 하여 rat의 난소 cDNA 라이브러리의 yeast two-hybrid screening을 시행하여 FOXL2 단백질과 상호작용을 하는 small ubiquitin-related modifier(SUMO)-conjugating E2 효소인 UBE2I 단백질을 찾았다. UBC9이라고도 알려진 UBE2I 단백질은 SUMO 변형 과정을 위한 필수적인 단백질이다. Sumoylation은 수 많은 전사인자의 전사능력의 조절을 포함하여 다양한 신호전달체계에 관여하는 번역 후 변형과정이다. 본 연구에서 인간세포인 293T 내에서 면역침전반응 실험을 통해 FOXL2와 UBE2I의 단백질-단백질간의 상호작용을 확인하고, FOXL2의 돌연변이형을 제작하여 yeast two-hybrid system을 이용해 UBE2I와 결합에 필요한 FOXL2의 부분을 규명하였다. 따라서, FOX2에 상호작용하는 UBE2I의 규명은 sumoylation에 의한 FOXL2의 새로운 조절 메커니즘을 시사한다.

We have cloned an LTP gene (PoLTP1) from poplar (Populus alba × P. tremula var. glandulosa) suspension cells and examined changes in its expression levels in response to various stresses and ABA treatment. The full-length PoLTP1 cDNA clone encodes a polypeptide of 116 amino acids with typical characteristics of LTPs, notably a conserved arrangement of cysteine residues. Southern blot analysis indicate that two or three copies of the PoLTP1 are present in the genome of the investigated hybrid poplar. In addition, northern analysis of samples from soil-grown plants indicate that PoLTP1 is tissue-specifically expressed in the leaves and flowers. The gene is significantly up-regulated by treatment with mannitol, NaCl and ABA, but not by either cold or wounding. These results indicate that PoLTP1 is involved in osmotic stress responses in poplar plants and suspension cells.

The aim of this study was to isolate chicken feather-degrading bacteria with high keratinolytic activity and to investigate cultural conditions affecting keratinolytic enzyme production by a selected isolate. A chicken feather-degrading bacterial strain CH3 was isolated from poultry wastes. Isolate CH3 degraded whole chicken feather completely within 3 days. On the basis of phenotypical and 16S rDNA studies, isolate CH3 was identified as Bacillus thuringiensis CH3. This strain is the first B. thuringiensis described as a feather degrader. The bacterium grew with an optimum at pH 8.0 and 37℃, where maximum keratinolytic activity was also observed. The composition of optimal medium for keratinolytic enzyme production was feather 0.1%, sucrose 0.7%, casein 0.3%, K2HPO4 0.03%, KH2PO4 0.04%, MgCl2 0.01% and NaCl 0.05%, respectively. The keratinolytic enzyme had a pH and temperature optima 9.0 and 45℃, respectively. The keratinolytic activity was inhibited ethylenediaminetetraacetic acid, phenylmethylsulfonyl fluoride, and metal ions like Hg2+, Cu2+ and Zn2+. The enzyme activated by Fe2+, dithiothreitol and 2-mercaptoethanol.