Mechanism of Dormancy in the Buds and Cambium of Eucommia ulmoides

This paper describes changes in the structure of buds and vascular cambium as well as in protein content of one-year-old dormant branches of Eucommia ulmoides Oliv. in water-culture conditions. Results confirm the existence of 2 quiescences (Q1, Q2) and 1 rest (R) phases in this tree during the dormancy period. In the R time, the E. ulmoides cambium was unable to reactivate even though the tree was subjected to exogenous IAA, suitable temperature or required luminosity. Furthermore, pistillate trees entered the dormant phase earlier than staminate ones. The protein content in the bark during Q1 increased significantly ( P < 0.01), but drastically decreased in the R period, before rising up again at the onset of Q2 ( P < 0.01). Even though the change pattern of protein content was similar, its occurrence is much earlier in staminate than in pistillate plants. SDS-PAGE revealed a 'special' protein band of 11.8 kD in the transitional Q1-R-Q2 stages. This 'special' protein bands would be related to the cambial dormancy and to the regulation of the Q1-R-Q2 transition.

A novel SATB1 binding site in the BCL2 promoter region possesses transcriptional regulatory function

BCL2 is a key regulator of apoptosis.Our previous work has demonstrated that special AT-rich sequence-binding protein 1 （SATB1） is positively correlated with BCL2 expression.In the present study,we report a new SATB1 binding site located between P1 and P2 promoters of the BCL2 gene.The candidate SATB1 binding sequence predicted by bioinformatic analysis was investigated in vitro and in vivo by electrophoretic gel mobility shift assays （EMSA） and chromatin immunoprecipitation （ChIP）.One 25-bp sequence,named SB1,was confirmed to be SATB1 binding site.The regulatory function of SB1 and its relevance to SATB1 were further examed with dual-luciferase reporter assay system in Jurkat cells.We found that SB1 could negatively regulate reporter gene activity.Mutation of SATB1 binding site further repressed the activity.Knockdown of SATB1 also enhanced this negative effect of SB1.Our data indicate that the SB1 sequence possesses negative transcriptional regulatory function and this function can be antagonized by SATB1.

SATB2-associated syndrome caused by a novel SATB2 mutation in a Chinese boy:A case report and literature review

BACKGROUND Special AT-rich sequence binding protein 2(SATB2)-associated syndrome(SAS;OMIM 612313)is an autosomal dominant disorder.Alterations in the SATB2 gene have been identified as causative.CASE SUMMARY We report a case of a 13-year-old Chinese boy with lifelong global developmental delay,speech and language delay,and intellectual disabilities.He had short stature and irregular dentition,but no other abnormal clinical findings.A de novo heterozygous nonsense point mutation was detected by genetic analysis in exon 6 of SATB2,c.687C>A(p.Y229X)(NCBI reference sequence:NM_001172509.2),and neither of his parents had the mutation.This mutation is the first reported and was evaluated as pathogenic according to the guidelines from the American College of Medical Genetics and Genomics.SAS was diagnosed,and special education performed.Our report of a SAS case in China caused by a SATB2 mutation expanded the genotype options for the disease.The heterogeneous manifestations can be induced by complicated pathogenic involvements and functions of SATB2 from reviewed literatures:(1)SATB2 haploinsufficiency;(2)the interference of truncated SATB2 protein to wild-type SATB2;and(3)different numerous genes regulated by SATB2 in brain and skeletal development in different developmental stages.CONCLUSION Global developmental delays are usually the initial presentations,and the diagnosis was challenging before other presentations occurred.Regular follow-up and genetic analysis can help to diagnose SAS early.Verification for genes affected by SATB2 mutations for heterogeneous manifestations may help to clarify the possible pathogenesis of SAS in the future.

The effect of baicalein on the expression of SATB1 in MDA-MB-231 cells

Baicalein had been proved to have anti-cancer activity in vitro and in vivo, including the inhibition of malignant proliferation, migration, adhesion and invasion of many kinds of cancer cells. The special AT-rich sequence binding protein 1 （SATB1） is a tissue-specific expression of nuclear matrix-binding protein and is reported to be a breast cancer ＂gene group organizer＂. Previous studies have shown that SATB1 is involved in the growth, metastasis and prognosis of breast cancer. The present study was aimed to investigate whether baicalein inhibits the proliferation and migration of MDA-MB-231 human breast cancer cells through down-regulation of the SATB1 expression. Methods： MDA-MB-231 cells were treated for 24 h, 48 h and 72 h with various concentrations of baicalein （0, 5, 10, 20, 40 and 80 pM） respectively. Then, the proliferation and migration of MDA-MB-231 cells following treatment with baicalein were determined using colorimetric 3-（4, 5-dimethylthia- zol-2-yl） 2, 5-diphenyltetrazolium bromide （MTT） and wound healing assays. Thereafter, western blot analysis was performed to detect the changes of SATB1 protein expression in MDA-MB-231 cells. Results： Along with the prolongation of time and increase of drug concentration, inhibitory effect of baicalein on proliferation and migration of MDA-MB-231 cells gradually in- creased, in a time.- and dose- dependent manner （P 〈 0.05）. Meanwhile, after treated with baicalein in different concentrations for 48 h, the level of SATB1 protein expression of MDA-MB-231 cells decreased obviously, in a dose-dependent manner （P 〈 0.05）. Conclusion： Baicalein inhibits breast cancer cell proliferation and suppresses its invasion and metastasis by reducing cell migration possibly by down-regulation of the SATB1 protein expression, indicating that baicalein is a potential therapeutic agent for human breast cancer.

Genomics of hepatitis B virus-related hepatocellular carcinoma and adjacent noncancerous tissues with cDNA microarray

Background Hepatocellular carcinoma （HCC） is a common primary cancer frequently associated with hepatitis B virus （HBV） infection. However, whether these identified genes are particularly associated with HBV-related HCC remains unknown. The aim of this study was to investigate the differential gene expression between HBV-related HCC tissues and adjacent noncancerous tissues. Methods cDNA microarray was used to detect the differential gene expression profile in the HBV-related HCC tissues and adjacent noncancerous tissues, and reverse transcription-polymerase chain reaction （RT-PCR） was performed to verify the differential expression of candidate genes obtained from cDNA microarray experiment. Results In this study, 1369 genes or expressed sequence tags （ESTs） including 121 genes or ESTs with at least two-fold expression alterations between cancerous and noncancerous tissues were identified. Special AT-rich sequence binding protein 1 （SATB-1） expression was positive in 73% （16/22） of cancerous tissues and negative （0/22） in all noncancerous tissues of HBV-related HCC patients. Transmembrane 4 superfamily member 1 （TM4SF-1） expression was positive in 86% （19/22） of cancerous tissues and negative （0/22） in all noncancerous tissues. Suppression of tumorigenicity 14 （ST-14） expression was positive in 73% （16/22） of noncancerous tissues in patients with HBV-related HCC and negative in all HCC tissues （0/22）. Conclusion This study provided the gene expression profile of HBV-related HCC and presented differential expression patterns of SATB-1, TM4SF-1 and ST-14 between cancerous and noncancerous tissues in patients with HBV-related HCC.