Two Faces of Cathepsin D: Physiological Guardian Angel and Pathological Demon

The background of this research is the fact that the management of improving teacher‟s professionalism is still not effective. The role of teacher as planner, implementer, and developer of curriculum is also not optimal. Management of teachers is needed because teachers have a significant role in the success of learning process. This research was aimed at knowing Guardian Angel‟s concept of teacher management suggested by Munif Chatib and how it develops according to him. The implementation of Guardian Angel model of teacher management was presented through a testimony and direct interviews with Guardian Angel‟s trainees. This research used qualitative approach by studying Munif Chatib‟s books and direct interviews. Data were analyzed with content analysis, which included: (1) literary study of Munif Chatib‟s books, (2) description of Guardian Angel model of teacher management by Munif Chatib. This research found that (1) the concept of Guardian Angel teacher management uses humanistic approach, especially in regard to schedules of consultation, teaching strategies, and assessment through four kinds of teacher reports, including reports of morals, creativity, lesson plan, and student‟s learning results; (2) the basis used is the cornerstone of the scientific human resources and philosophical foundation that teachers carry out the work of teaching, which includes planning, teaching, evaluating, and learning. The first three points are teacher‟s obligations, while the last is their right. Penelitian ini dilatarbelakangi adanya keprihatinan manajemenpeningkatan profesionalitas guru yang belum berjalan efektif. Peranan guru sebagai perencana, pelaksana dan pengembang kurikulum yang belum optimal. Manajemen guru diperlukan mengingat bahwa peran guru amat signifikan bagi setiap keberhasilan proses pembelajaran.Penelitian ini mengungkap tentang manajemen guru Guardian Angel menurut Munif Chatib. Penelitian ini bertujuan untuk mengetahui konsep manajemen guru model Guardian Angel menurut Munif Chatib, dan berkembangannya Guardian Angel dalam pemikiran Munif Chatib. Implementasi manajemen guru model Guardian Angel dihadirkan melalui testimoni dan wawancara langsung dengan peserta pelatihan Guardian Angel. Penelitian ini menggunakan pendekatan kualitatif, dengan melakukan kajian terhadap buku - buku karya Munif Chatib dan wawancara langsung. Teknik anaisis data content analysis. Analisis meliputi: (1) kajian pustaka buku-buku karya Munif Chatib, (2) mendeskripsikan manajemen guru model Guardian Angel dalam pemikiran Munif Chatib.Hasil penelitian menunjukkan bahwa: (1) konsep model manajemen guru Guardian Angel menggunakan pola pendekatan manajemen humanis, terutama dalam jadwal konsultasi, strategi mengajar dan penilaian melalui empat rapor guru, yaitu rapor akhlak, rapor kreativitas, rapor lesson plan dan rapor hasil belajar siswa (2) landasan yang digunakan adalah landasan keilmuan sumber daya manusia dan landasan filosofi bahwa profesi guru mengemban pekerjaan manajemen, yaitu perencanaan , mengajar dan mengevaluasi dan belajar. Tiga hal pertama difahami sebagai kewajiban, sedangkan belajar dimaknai sebagai hak bagi seorang guru (3) Guardian Angel sebagai manajemen quality control yang meliputi: lesson plan, konsultasi, observasi dan umpan balik.

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Faculty Opinions recommendation of Requirement of the human GARP complex for mannose 6-phosphate-receptor-dependent sorting of cathepsin D to lysosomes.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718529687.793498665 ◽

2014 ◽

Author(s):

Paul Gleeson

Keyword(s):

Cathepsin D ◽

Mannose 6 Phosphate ◽

Garp Complex

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Effect of Temperature and pH on the Secondary Structure and Denaturation Process of Jumbo Squid Hepatopancreas Cathepsin D.

Protein and Peptide Letters ◽

10.2174/0929866526666190405124353 ◽

2019 ◽

Vol 26 (7) ◽

pp. 532-541 ◽

Cited By ~ 1

Author(s):

Cadena-Cadena Francisco ◽

Cárdenas-López José Luis ◽

Ezquerra-Brauer Josafat Marina ◽

Cinco-Moroyoqui Francisco Javier ◽

López-Zavala Alonso Alexis ◽

...

Keyword(s):

Circular Dichroism ◽

Secondary Structure ◽

Cathepsin D ◽

Thermal Denaturation ◽

Protein Denaturation ◽

Marine Organisms ◽

Effect Of Temperature ◽

Jumbo Squid ◽

Α Helix ◽

Circular Dichroïsm

Background: Cathepsin D is a lysosomal enzyme that is found in all organisms acting in protein turnover, in humans it is present in some types of carcinomas, and it has a high activity in Parkinson's disease and a low activity in Alzheimer disease. In marine organisms, most of the research has been limited to corroborate the presence of this enzyme. It is known that cathepsin D of some marine organisms has a low thermostability and that it has the ability to have activity at very acidic pH. Cathepsin D of the Jumbo squid (Dosidicus gigas) hepatopancreas was purified and partially characterized. The secondary structure of these enzymes is highly conserved so the role of temperature and pH in the secondary structure and in protein denaturation is of great importance in the study of enzymes. The secondary structure of cathepsin D from jumbo squid hepatopancreas was determined by means of circular dichroism spectroscopy. Objective: In this article, our purpose was to determine the secondary structure of the enzyme and how it is affected by subjecting it to different temperature and pH conditions. Methods: Circular dichroism technique was used to measure the modifications of the secondary structure of cathepsin D when subjected to different treatments. The methodology consisted in dissecting the hepatopancreas of squid and freeze drying it. Then a crude extract was prepared by mixing 1: 1 hepatopancreas with assay buffer, the purification was in two steps; the first step consisted of using an ultrafiltration membrane with a molecular cut of 50 kDa, and the second step, a pepstatin agarose resin was used to purification the enzyme. Once the enzyme was purified, the purity was corroborated with SDS PAGE electrophoresis, isoelectric point and zymogram. Circular dichroism is carried out by placing the sample with a concentration of 0.125 mg / mL in a 3 mL quartz cell. The results were obtained in mdeg (millidegrees) and transformed to mean ellipticity per residue, using 111 g/mol molecular weight/residue as average. Secondary-structure estimation from the far-UV CD spectra was calculated using K2D Dichroweb software. Results: It was found that α helix decreases at temperatures above 50 °C and above pH 4. Heating the enzyme above 70°C maintains a low percentage of α helix and increases β sheet. Far-UV CD measurements of cathepsin D showed irreversible thermal denaturation. The process was strongly dependent on the heating rate, accompanied by a process of oligomerization of the protein that appears when the sample is heated, and maintained a certain time at this temperature. An amount typically between 3 and 4% α helix of their secondary structure remains unchanged. It is consistent with an unfolding process kinetically controlled due to the presence of an irreversible reaction. The secondary structure depends on pH, and a pH above 4 causes α helix structures to be modified. Conclusion: In conclusion, cathepsin D from jumbo squid hepatopancreas showed retaining up to 4% α helix at 80°C. The thermal denaturation of cathepsin D at pH 3.5 is under kinetic control and follows an irreversible model.

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