Identification of novel partner proteins of PCBP1 / 北京大学学报(医学版)

Objective: PCBP1 is a family member of heterogeneous nuclear ribonucleoproteins (hnRNPs) that belong to RNA-binding proteins and bear three KH domains. The protein plays a pivotal role in post-transcriptional regulation for RNA metabolism and RNA function in gene expression. We hy-pothesized and were going to identify that the regulatory function of PCBP1 is performed through different complexes of proteins that include PCBP1. Methods: To test our hypothesis, approaches of protein wal-king with a yeast two-hybrid system (Y2H), pulling down in yeasts, co-immunoprecipitation and immu-nofluorescent microscopy assay were employed in this study. The PCBP1 was used as the initial "walker" to search for its interaction partner(s). Results: Candidate proteins including MYL6, PECAM1, CSH1,RAB7, p57KIP2, ACTG1, RBMS1 and PSG4-1ike were identified with selection mediums and preceding methods. Conclusion: With these candidate protein molecules, some protein complexes associating with PCBP1 are proposed, which may help in a better understanding of physiological functions of PCBP1 and proved evidence that PCBP1 is involved in variant biological pathways.

Genotype-phenotype analyses of classic neuronal ceroid lipofuscinosis (NCLs): genetic predictions from clinical and pathological findings / 北京大学学报(医学版)

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.