JNK3 involvement in nerve cell apoptosis and neurofunctional recovery after traumatic brain injury

Increasing evidence has revealed that the activation of the JNK pathway participates In apoptosis o1 nerve cells and neurological function recovery after traumatic brain injury. However, which genes inI the JNK family are activated and their role in traumatic brain injury remain unclear. Therefore, in this study, in situ end labeling, reverse transcription-PCR and neurological function assessment were adopted to investigate the alteration of JNK1, JNK2 and JNK3 gene expression in cerebral injured rats, and their role in celt apoptosis and neurological function restoration. Results showed that JNK3 expression significantly decreased at 1 and 6 hours and 1 and 7 days post injury, but that JNK1 and JNK2 expression remained unchanged. In addition, the number of apoptotic nerve cells surrounding the injured cerebral cortex gradually reduced over time post injury. The Neurological Severity Scores gradually decreased over 1,3, 5, 14 and 28 days post injury. These findings suggested that JNK3 expression was downregulated at early stages of brain injury, which may be associated with apoptosis of nerve cells. Downregulation of JNK3 expression may promote the recovery of neurological function following traumatic brain injury.

The expression of Fas, FasL and their biological behavior in human cervical carcinoma

Objective： To investigate the relationship between the expression of Fas and Fas ligand （FasL） and its biological behavior in human cervix carcinoma. Methods： Immunohistochemisty technique was used to detect the expression of Fas and FasL in 47 cases of cervical carcinoma, 16 cases of cervical interaepithelial neoplasia, 10 cases of chronic cervicitis and 10 cases of normal cervix. TUNEL technique was used to observe the apoptic cells in 47 cases of cervical carcinoma. Retrospective study was carried out to find the relationship between the expression of Fas and FasL and cell apoptosis, clinical stage, pathological classification, lymph node metastasis, prognosis and age. Results： The expression of Fas and FasL was significantly different in different cervix （P 〈 0.01）, and also related to the degree of differentiation, lymph node metastasis and prognosis （P 〈 0.05）. But had no relation with clinical stage or age （P 〉 0.05） ; Cervix carcinoma cells apoptosis in different pathological classification appeared negative relation （Rs=-0.35, P 〈 0.05 ）. Cervix carcinoma cell apoptosis was significantly higher in Fas-positive and FasL- positive than that in Fas-negative and FasL-negative （P 〈 0.05）. By retrospective investigation, Fas-negative and FasL-positive were related to poor prognoses of the patients with cervical carcinoma （P 〈 0.05 ）. Conclusion： The development of apoptosis in cervix carcinoma has a promoting regulation function in Fas and FasL expression. Gene treatment can alter apoptosis abnormality, thus induce apoptosis in cancerous cell expressing Fas and FasL. Fas or FasL may be taken as a marker in the prognostic character- ization.

Programmed cell death may act as a surveillance mechanism to safeguard male gametophyte development in Arabidopsis

Programmed cell death(PCD)plays an important role in plant growth and development as well as in stress responses.During male gametophyte development,it has been proposed that PCD may act as a cellular surveillance mechanism to ensure successful progression of male gametogenesis,and this suicide protective machinery is repressed under favorable growth conditions.However,the regulatory mechanism of male gametophyte-specific PCD remains unknown.Here,we report the use of a TdT-mediated dUTP nick-end labelingbased strategy for genetic screening of Arabidopsis mutants that present PCD phenotype during male gametophyte development.By using this approach,we identified 12 mutants,designated as pcd in male gametogenesis(pig).pig mutants are defective at various stages of male gametophyte development,among which nine pig mutants show a microspore-specific PCD phenotype occurring mainly around pollen mitosis I or the bicellular stage.The PIG1 gene was identified by map-based cloning,and was found to be identical to ATAXIA TELANGIECTASIA MUTATED(ATM),a highly conserved gene in eukaryotes and a key regulator of the DNA damage response.Our results suggest that PCD may act as a general mechanism to safeguard the entire process of male gametophyte development.