Objective: Batten disease （BD）, the juvenile form of neuronal ceroid lipofuscinosis （NCLs）, is pathological characterized by finding lysosomal storage of autofluorescent lipofuscins with unique ultrastructural profiles. The gene underlying BD is designated CLN3 and encodes a protein, Battenin, of unknown function that localizes in lysosomes and/or mitochondria. Previously, we hypothesized that Battenin associates with other membrane protein（s） to form a membrane complex. Dysfunction of this complex could result in the pathological changes of BD, and possibly in other NCLs. Two such membranous proteins, the slow and fast Battenin-interactive proteins （BIPs and BIPf） of unknown functions, have been identified. In this study, we have characterized the functional domains of Battenin that interact with both BIP proteins. Methods: Protein-protein interactions with a yeast two-hybrid system were employed. A “deletion assay” was employed to localize the interactive segment（s）. Different lengths of cDNA sequences lacking exon 1-5 were used to express CLN3-encoded proteins lacking N-terminal segments in the yeast two-hybrid system. N-terminal exons of CLN3 were deleted with PCR-cloning strategies.Results: We eliminated the possibility of interacting domains from the exon 7-encoded region because both Battenin and mBattenin interact with the BIP proteins. We have shown that peptide sequences encoded by exons 2 and 4 of CLN3 gene include the functional domains by which Battenin interacts with the BIP proteins. Conclusion: Our studies provide evidence that the N-terminus of Battenin is the functional domain for these protein interactions.
Dorota N. MOROZIEWICZWeina JURocksheng ZHONGNanbert ZHONG
Objective:Genotype-phenotype associations were studied in 517 subjects clinically affected by classical neuronal ceroid lipofuscinosis (NCL). Methods:Genetic loci CLN1-3 were analyzed in regard to age of onset, initial neurological symptoms, and electron microscope (EM) profiles. Results: The most common initial symptom leading to a clinical evaluation was developmental delay (30%) in NCL1, seizures (42.4%) in NCL2, and vision problems (53.5%) in NCL3. Eighty-two percent of NCL1 cases had granular osmiophilic deposits (GRODs) or mixed-GROD-containing EM profiles; 94% of NCL2 cases had curvilinear (CV) or mixed-CV-containing profiles; and 91% of NCL3 had fingerprint (FP) or mixed-FP-containing profiles. The mixed-type EM profile was found in approximately one-third of the NCL cases. DNA mutations within a specific CLN gene were further correlated with NCL phenotypes. Seizures were noticed to associate with common mutations 523G>A and 636C>T of CLN2 in NCL2 but not with common mutations 223G>A and 451C>T of CLN1 in NCL1. Vision loss was the initial symptom in all types of mutations in NCL3. Surprisingly, our data showed that the age of onset was atypical in 51.3% of NCL1 (infantile form) cases, 19.7% of NCL2 (late-infantile form) cases, and 42.8% of NCL3 (juvenile form) cases.Conclusion:Our data provide an overall picture regarding the clinical recognition of classical childhood NCLs. This may assist in the prediction and genetic identification of NCL1-3 via their characteristic clinical features.
Weina JUAnetta WRONSKADorota N. MOROZIEWICZRocksheng ZHONGNatalia WISNIEWSKIAnna JURKIEWICZMichael FIORYKrystyna E. WISNIEWSKILance JOHNSTONW. Ted BROWNNanbert ZHONG
Hutch inson-G ilford早老症(HGPS)为一种极为罕见的遗传性疾病,发生率1/8000000,特征性表现为患儿以极快速度衰老,多数死于冠脉病变引起的心肌梗死或广泛动脉粥样硬化导致的卒中,平均寿命13岁。绝大多数HGPS病例病因为LMNA基因第11个外显子发生点突变(G608G),生成的突变lam in A由显性负效应造成细胞核结构和功能受损。目前该病已有几种动物模型,实验性治疗可以在体外将出泡的细胞核恢复正常。HGPS是研究衰老和心血管疾病机制的一个极好的模型。
