Long Non-Coding RNAs Associated with Ribosomes in Human Adipose-Derived Stem Cells: From RNAs to Microproteins.

Ribosome profiling reveals the translational dynamics of mRNAs by capturing a ribosomal footprint snapshot. Growing evidence shows that several long non-coding RNAs (lncRNAs) contain small open reading frames (smORFs) that are translated into functional peptides. The difficulty in identifying bona-fide translated smORFs is a constant challenge in experimental and bioinformatics fields due to their unconventional characteristics. This motivated us to isolate human adipose-derived stem cells (hASC) from adipose tissue and perform a ribosome profiling followed by bioinformatics analysis of transcriptome, translatome, and ribosome-protected fragments of lncRNAs. Here, we demonstrated that 222 lncRNAs were associated with the translational machinery in hASC, including the already demonstrated lncRNAs coding microproteins. The ribosomal occupancy of some transcripts was consistent with the translation of smORFs. In conclusion, we were able to identify a subset of 15 lncRNAs containing 35 smORFs that likely encode functional microproteins, including four previously demonstrated smORF-derived microproteins, suggesting a possible dual role of these lncRNAs in hASC self-renewal.

Microproteínas urinarias marcadoras de daño renal en pacientes con glomerulopatías / Urinary microprotein markers of renal disease in patients with glomerulopathies / Microproteínas urinárias marcadoras de lesão renal em pacientes com glomerulopatias

En las glomerulopatías, las Microproteínas Urinarias (MU) se eliminan por distintos mecanismos fisiopatológicos. El objetivo del trabajo fue correlacionar las MU con el daño histológico evaluado en la punción biopsia renal (PBR) de pacientes con diversas glomerulopatías. Se estudiaron 44 orinas espontáneas (33 mujeres y 11 varones) entre 18 y 71 años de edad, por el método de electroforesis bidimensional de uso clínico (2D UC). Las proteínas identificadas se dividieron en 5 grupos y se compararon con lesiones vasculares, glomerulares y túbulointersticiales; estas dos últimas se dividieron en crónicas y agudas. Las del grupo identificado como las "Tres Marías" (fragmento de 35 kDa de la proteína inhibidor de tripsina cadena pesada H4, Prostaglandina H2 sintasa y fragmento de 23 kDa del Perlecan) resultaron no ser marcadoras de daño tubular, sino de alteraciones glomerulares crónicas. La presencia de las mismas, con proteinuria, se observa antes de la caída de la filtración glomerular (<60 mL/min) y correlaciona con el 30% de glomérulos totalmente esclerosados (p<0,001). El grupo Triángulo, en la glomerulopatía, contiene a la Alfa-1 microglobulina (A1m) y a las cadenas livianas libres de Inmunoglobulinas (CLL), e indica lesión glomerular activa. Por lo tanto, las MU en glomerulopatías, responden a lesiones glomerulares activas y crónicas. Los perfiles proteicos urinarios hallados por la 2D UC permitieron conocer el grado de lesión en los distintos compartimentos renales.

In Glomerulopathies, urinary microproteins (UM) are eliminated by different pathophysiological mechanisms. The objective of this work was to correlate the UM with the histological damage evaluated in the renal biopsy through puncture of patients with various glomerular diseases. Forty-four urine samples (33 females, 11 males) aged 18 to 71 years old were studied by the method of two-dimensional electrophoresis of clinical use (2D UC). The identified proteins were divided into 5 groups and were compared with vascular injury, glomerular and tubulointerstitial injury, the latter in chronic and acute cases. The group identified as the "Three Marias" (fragment 35 kDa protein trypsin inhibitor heavy chain H4, prostaglandin H2 synthase and 23 kDa fragment of Perlecan), was not found as marker of tubular damage, but it was found in chronic glomerular disorders. The presence of this same group -with proteinuria- is seen before the collapse of the glomerular filtration rate (<60 mL/min) and it is correlated with 30% of fully sclerotic glomeruli (p<0.001). In glomerulopathy, the Triangle group: Alpha-1 microglobulin (A1m) and free Immunoglobulin light chains (FLC), indicates active glomerular injury. Therefore, the UM in glomerular diseases, respond to active and chronic glomerular lesions. Urinary protein profiles found by the 2D UC made it possible to know the degree of renal injury in different renal compartments.

Nas glomerulopatias, as Micro proteínas Urinárias (MU) são eliminadas através de diferentes mecanismos fisiológicos. O objetivo do trabalho foi relacionar as MU com o dano histológico avaliado na punção biópsia renal (PBR) de pacientes com diversas glomerulopatias. Foram estudadas 44 urinas espontâneas (33 mulheres e 11 homens entre 18 e 71 anos de idade), pelo método de eletroforese bidimensional de uso clínico (2D UC). As proteínas identificadas foram divididas em 5 grupos e comparadas com lesões vasculares, glomerulares e túbulo-intersticiais, estas duas últimas classificadas em crônicas e agudas. O grupo identificado como as "Três Marias" (fragmento de 35 kDa da proteína inibidora de tripsina cadeia pesada H4, Prostaglandina H2 sintase e fragmento de 23 kDa do Perlecam), resultaram não ser marcadoras de dano tubular, mas de alterações glomerulares crônicas. A presença de tais proteínas, com proteinúria, observa-se antes da queda da filtragem glomerular (<60 mL/min) e correlaciona com 30% de glomérulos totalmente esclerosados (p<0,001). O grupo Triângulo, na glomerulopatia, que contém a Alfa-1 microglobulina (A1m) e as cadeias leves livres de Imunoglobulinas (CLL) indicam lesão glomerular ativa. Portanto, as MU em glomerulopatias respondem a lesões glomerulares ativas e crônicas. Os perfis proteicos urinários encontrados pela 2D UC permitiram conhecer o grau de lesão nos diferentes compartimentos renais.